Brad Rockwell is the executive manager of operations at the Kauai Island Utility Cooperative in Hawaii. In this episode, Robert talks to Rockwell about how his co-op has achieved high penetration of renewable electricity – it now gets about 60% of its electricity from biomass, hydropower and solar – his grid’s use of battery storage, why it will still need oil-fired generators, and the future of renewable electricity on the other Hawaiian islands.
Brad Rockwell is the executive manager of operations at the Kauai Island Utility Cooperative in Hawaii. In this episode, Robert talks to Rockwell about how his co-op has achieved high penetration of renewable electricity – it now gets about 60% of its electricity from biomass, hydropower and solar – his grid’s use of battery storage, why it will still need oil-fired generators, and the future of renewable electricity on the other Hawaiian islands.
Robert Bryce 0:05
Hi, and welcome to the power hungry podcast. I'm Robert Bryce. On this podcast we talk about energy, power, innovation and politics. And my guest today, I'm happy to introduce is Brad Rockwell, the executive manager of operations at the Hawaii Island utility cooperative. Brad, thanks for being with me today. And with us today.
Brad Rockwell 0:26
Well, thank you for having me, Robert. Happy to be here.
Robert Bryce 0:28
So we're going to talk about the the quiet Island utility cooperative and how it's unique in that it runs primarily or a lot of the time on 100% renewables. But, Brad, I could introduce you, but I prefer to let my guests introduce themselves. So if you don't mind, give us a quick introduction, as though you just arrived at a party and don't know anyone there. Give us the you know, the 60 92nd intro, if you don't mind,
Brad Rockwell 0:56
thanks to the short version is just I'm a conventional energy conventional power guy that, you know, study this stuff in college and practiced it a little bit in the Navy, on active duty and in private industry with some companies like GE and the like, and somehow found myself in the middle of the Pacific in a place where renewables made a lot of sense for financial reasons, because there are other options were pretty limited. So an unlikely person to be in the middle of the or I should say, on the tip of the spear, I guess. So the renewable, high penetration renewables and especially with solar solar has really been where we've done a lot over here. And, and it's been exciting, it probably would have been boring if I just come over and run conventional oil power plants. So it's been fun. But I definitely see the value of both and then sort of an everything on the table kind of strategy guy when it comes to energy. I don't think there's, I think I think there's trade offs with anything need to have all options available?
Robert Bryce 2:02
Sure. Well, let's jump right in and talk about that. Because, you know, like a lot of people in the power sector, especially on the engineering side, your former Navy guy, which I didn't quite understand until I realized, oh, every ship has its own electrical system. So they need electricians and people who know how to manage them. But the cool Island story, I think is while utility cooperative story is really an interesting one for a lot of reasons, among them, that it's a relatively new Co Op. But I want to cut to the reason why we're talking and that is that you're able to utilize a higher penetration of renewables than any other electric grid that I know of. So on average, tell me what what is that penetration? And what's the mix that you're using?
Brad Rockwell 2:47
Yeah, and I don't know that we're higher than anywhere. I know, just to caveat that I know places like Iceland, I think are, you know, doing it with a lot of geothermal and large hydro, and but, you know, that said, you know, every place is different. And for us, we're operating almost every day for multiple hours at a time at 100%. Renewable. And when we're doing that we have a little bit of hydro, a little bit of biomass, but about 80 to 85% is coming from solar, with some of that back firmed up by storage. on an annual basis, we're running about 65%. And that's increasing, we're about to bring on another month or so will bring on another large solar and storage project, which could push us up over 70% on an annual basis.
Robert Bryce 3:36
So and so you can regular solar PV, it would connected to storage and what what's the chemistry on the batteries? What kind of batteries are using and how big, how big is the storage system?
Brad Rockwell 3:50
They're all lithium ion. And so we have really two large solar and storage plants. One is a 13 megawatt Tesla project and it's got a four hours of storage at the full 13 megawatts, so 52 megawatt hours. It's actually rated for about 60. And then we have a, an A s project, that's a 20 megawatt AC, solar PV. And it's got, again, the full capability on the power side of storage. So it's 20 megawatt battery for five hours, so it's 100 megawatt hour battery. And then this next project we're bringing on in a month is a 14 megawatt solar project AC, these are all AC ratings and in 14 megawatt battery with five hours again. So that's a 70 megawatt hour battery. So when you add it all up, we're, you know, 230 megawatt hours of storage for an island that averages you know, 50 megawatts of demand. 24 seven, we peak at about 80 megawatts in the evening. And we get down to about 35 in the wee hours in the morning.
Robert Bryce 5:04
But 50 is an average 70 in the 70s is of the high and then half that as the low roughly. Right. What, and I've heard you present before at a cooperative meeting, I'm not sure where it was exactly that we met. But I was intrigued because you're the it's the really the mix, you're you were largely dependent on diesel, diesel fired generators for four years, right when the CO operative first was formed. And, and that's the other thing that's interesting is about the CO operative is that it's pretty new. It's less than 20 years old. Is that right?
Brad Rockwell 5:38
That's, that's true. 2002 we started? Yeah, so we we had, you know, the history of electricity in Hawaii, and Hawaii specifically is all ties back to the sugar plantations. You know, that's, that's, that's where it all came from. And they traditionally had small hydro plants up in the mountains, delivering water to the sugarcane fields, and then they were using the gas to generate power through a steam turbine. So it was we used to be virtually all renewable. And, and then they started mixing in some diesel generators, you know, in the 50s, and 60s and 70s. And then sugar plantations sort of couldn't compete on the world market. And they all started closing down in the 80s and 90s. And so what do you how are you going to replace that power? Well, oil was cheap, then put in diesel generators, we don't have the luxury of having natural gas or, you know, large hydro dams type of thing. And, and actually, coal and nuclear fission power plants are specifically prohibited in Hawaii State Constitution. So there you have it, most of where the continent gets its power from us. We don't really have those choices here.
Robert Bryce 6:52
I didn't, I didn't realize that that coal is specifically prohibited for
Brad Rockwell 6:57
any new coal plants. There is one coal plants on a wahoo. But it's PPA runs out at the end of 2022. And they are not going to allow it to extend. So that has to be replaced.
Robert Bryce 7:08
Sure. Well, and the I know that Hawaii as a whole has a 50 per will 100% renewable mandate by 2050. Right. So
Brad Rockwell 7:19
Robert Bryce 7:21
And so co Island may be the first one that hits that target. And and what's interesting, too, is you're doing it all without any wind energy. Is that right?
Brad Rockwell 7:31
That's true. Yeah, wind has been challenged here on Hawaii for sort of that when I saw it, and I call the trifecta we have threatened and endangered seabirds and the other islands don't have they've already been sort of the populations have been decimated already there. You don't have relatively speaking as good a wind regimes as some of the other islands in Hawaii, because our mountains are not as tall. To put it simply, and we don't really have any willing landowners that want the wind turbines over here. So we haven't really pushed for it. And, and frankly, solar seems to be much more acceptable by the community. And the price point is better for us at the scale we can do. So our grid is relatively smaller than the other islands, we're about a third of what Big Island and Maui peak said and we're about a 12 to a 15th of a watt who are most of the people of
Robert Bryce 8:22
Sure. And so your tell me how many meters I know that in the in the CO operative world will and investor on utilities or everybody wants to know well, how big is the utility? How many meters do you have? And then what is the average consumption? Because this is the other part I think of the that makes your co operative in your operation unique is that you're well there are many things right you're an island first and but also your your electricity consumption per meter is still relatively low. Run me through those numbers,
Brad Rockwell 8:51
you know that? Yeah, so we're about 34,000 meters. And our average residential use monthly is about 500 kilowatt hours per month, which is you know, probably close to half of what people on the mainland use and that's that's because the stable climate here, nobody has heat in their homes and very few people even have air conditioning. So you know, the climates very stable. It's never too hot, never, never cold. And and people spend a lot of time outside, you know, because the weather's good year round. And we don't have any large industry. So yeah
Robert Bryce 9:33
500 kilowatt hours per meter and that's not per capita, which here on average in the United States per capita consumption is 11,000 12,000 kilowatt hours per person. Now, you figure what is it two or 2.3 people per household? Exactly, capita consumption is going to be even lower than that, that that number so. So you you have relatively modest level. And then the other part that I think is interesting is that and solar and storage are clearly gaining traction, there's no doubt on, you know, all over the world. But you're still but you're using biomass and biomass fired plant. So run me through the different generators that you have because you have a lead of different generators using different fuels. And you're using at different times. Can you run me through those? Those that that outline those those facilities for me?
Brad Rockwell 10:27
Sure, sure. We have our port Allen power plant is sort of our historical, you know, started in the early 1960s. And it's got about 13 different units there. So there's nine diesel generators of different sizes. Some five locomotive type diesel's we've got for work Silla type, you know, diesel's marine diesel's, we've got two GE frame gas turbines. So those are like the heavy industrial gas turbines, but holder technology, nothing to do and they're smaller. They're about 20 megawatts each. And, and then we have a steam turbine, also at that port Allen plant that just has an oil fired boiler. But it calls can also take waste heat from the gas turbines. Our other fossil plant is our coppia power station. That's our newest unit. That was the reason I came to coai was to help get that going. And it came online in 2002. Right as a co op was forming. And that burns either diesel or naphtha, but it's an aero derivative gas turbine. And we've actually
Robert Bryce 11:36
an aero derivative, meaning it's similar to what you find on a jet engine.
Brad Rockwell 11:40
Is that Exactly, yeah. So I mean, the point there is very thin casings, it's a light unit. You know, when you do an overhaul on that thing, you actually fly it to the shop, where is that the frame type gas turbines have these very thick cast iron casings, and you can't ever ship that off. You do that work on site? I see. And then, and we've added a synchronous condensing capability to that aeroderivative gas turbine, which is very critical to our ability to operate at 100% renewables we can get into later, but those are two conventional.
Robert Bryce 12:13
Well, if you don't mind, I'd like to stay there for just a second because I think that that's an interesting part of the the the the in the ability of grids to use high penetration renewables is to require synchronous generation Tell me why that matters. What is the synchronous generation capability do?
Brad Rockwell 12:32
Yeah, the critical. Yeah, so if you break it all down, you know, I mean, high penetration or renewables in a place like Python, for example. And I'm not trying to, you know, shortchange them or anything. But you know, when you're doing it with Hydro and geothermal, you've still got synchronous machines that are essentially it's just a cleaner fuel, if you will. And so what what synchronous machines do is they provide rotating mass, they provide inertia to the grid, they provide amazing fault, correct potential. So when there's a fault on the grid, the transit, you know, line comes down is the simplest example, voltage sags. And you need something to provide overcurrent, which will trip relay protective devices and clear that, that fault so that that line is not hot when it falls to the ground. And so these rotating machines have an amazing capability to provide that overcurrent, that inverter base generation does not. Same with inertia. And then there's also the voltage support, those are, those are kind of the three main things. But there's also sort of another thing that I'm realizing and try not to get too technical. But the way you measure frequency, you know, typically rotating machines, they're measuring frequency by the speed of the shaft, they've got a tack, ometer and a gear tooth. And it's quite simple when that thing slows down because of a fault. You can see it right there on this high speed tech ometer. And the controls. Well, an inverter doesn't have anything rotating. And so inverters are trying to measure grid frequency based on the sine wave of you know, that AC signal and during follow up 6060
Robert Bryce 14:14
cycles per second going back and
Brad Rockwell 14:16
right back and forth, right? Yeah, exactly. And when a fault condition occurs, that sine wave can be somewhat distorted. And so you know, the inverter may not have an accurate understanding of what frequency is. And now you're asking that inverter to respond to a change in frequency, it can be somewhat difficult.
Robert Bryce 14:37
So if I can see if I can interrupt it the way I think of it, and if I've got it wrong, correct me but the grid inertia is is critical because it's similar to water pressure. I think that that's the that's the way I think about it right? That you need the grid depend the stability of the grid is depends on that ability of the machines that are driving it to have a certain amount of Pressure behind the electricity. And I know it's an imperfect analogy. But is that fair?
Brad Rockwell 15:04
I like to I think the better analogy is, water pressure is more akin to voltage. And inertia is more like, you know, your inertia, you know, the definition of inertia is probably like the resistance to change. So, you're going along, it's steady state, everything's fine. A fault occurs, how quickly is frequency going to deviate from 60 hertz. Now, when this fault occurs, if you have a light light inertia system, like we have on a small island at grid frequency is going to want to change very quickly. And pretty soon, you could find yourself getting into unstable conditions or having to under frequency load shed to protect the system on the mainland, you know, clearly, when a line comes down, somewhere on the bulk electrical system on the continent, it doesn't cause frequency to move very much, let's say huge system with lots of inertia over here, it will cause frequency to move, you know, somewhat quickly. So that's the best way to describe it at that resistance to change, you want to keep steady state, like a ship moving through the ocean, you know, you've got this massive inertia, but the voltage of the system is critical. That's kind of like the pressure in your water hose.
Unknown Speaker 16:16
Brad Rockwell 16:16
you don't have the pressure, you can't deliver the flow. If you don't have the voltage, you can't deliver the current to the customer.
Robert Bryce 16:23
And the synchronous condensers that you mentioned, are synchronous generators. I'm going to make sure I get them.
Brad Rockwell 16:29
Well, we talked about bolts. So synchronous generators are just all the rotating machines when you actually synchronous condenser is you don't necessarily have a prime mover behind the generator anymore. You can but you're not delivering real power with a synchronous condenser. you're delivering reactive power navigation, the bar discussion? Right.
Robert Bryce 16:51
Okay. But But the point then we we've taken a tangent here a little bit left technical left turn, but I think it's important for what I am increasingly understanding is that the one of you renewables have many attributes, but one of the things that is one of their downsides is that issue of making sure that you have enough inertia on the system that the system then can maintain that steady state throughout any kind of change in in demand. Yeah, so anyway, I interrupted you after you were going through the different different different generation systems that you have. So we've covered pretty much I think, the fossils side of it, right? And then you have Hydro and solar, right?
Brad Rockwell 17:35
Yep. Yep, we have? Well, we have the biomass that you mentioned. So the biomass is interesting. I'll just talk about that briefly. That was really our first new renewable, you know, this was this, this PPA was signed back in 2009. Well, before solar PV was at a good price point, even for us here in Hawaii. And so we were struggling to how to how to transition away from being so dependent on oil as the mid 2000s. You know, the early part of this century saw oil spikes up over well over $100 a barrel, we knew we had to transition. So that's that's how the biomass plant came to be. But it's a small scale. Plant, it's only seven megawatts. It's very expensive to do biomass at that scale. But it is interesting because it's a it's a closed loop biomass to growing a sustainable forestry plantation and harvesting a part of it. Another neat feature about it is they actually spent the first few years while the plantation was getting established clearing the island of this very invasive, aggressive tree species called lbz. That's been nice. We're seeing you know, large stands of these albizia getting taken away and chipped up to generate power. So that's the biomass our hydro plants are essentially like
Robert Bryce 18:55
it used to be and just to be clear, if I can on the buyer, man, so you're, you're not using our vizia to fuel the biomass. You're, you're you're you're growing a different kind of tree. What kind of tree is
Brad Rockwell 19:05
it? It's a it's a version of eucalyptus. I see. Okay, and it's been a managed plantation, so won't spread around. Yeah,
Robert Bryce 19:12
I see. Okay, because this is one of the few I mean, biomass has been very controversial in Europe. And in fact, hauling American wood chips to Europe to burn in, in their power plants is one of the examples of, you know, many critics, and I think they're right is that well, this makes no sense. You've got to have high carbon footprint, moving just those woodchips around but because it qualifies as renewable. In Europe, that's the route that they're taking. But what that but that even though it's only seven megawatts To me, that's one of the other interesting things about your system is that this is one of your building blocks that you are depending on and it sounds like it's working pretty well.
Brad Rockwell 19:51
Yeah, no, it is working well. And so like I said, it's kind of a it's a higher cost, but it's a relatively small part of our mix. About 10 or 11%. So, you know, it's a synchronous machine, it's the same turban. So that's that's got some value. But there's a, there's a biomass plants on the Big Island that people are fighting, which we can get into later as well when we talk about other things like that, and how people fight renewables in different places. So the hydro plants are all small hydro, the largest single unit is six megawatts, but most of them are actually half a megawatt or a megawatt those are, you know, legacy sugar plantations, or, you know, 100 year old hydro turbines that, in fact, the first power on the island was this hydro power plant that's still in operation, it started in 1905. And provided power, they built a transmission line across the island. So from the north shore of the island, from this hydro plant, transmission line across the island to power these huge irrigation pumps to, to provide water to the sugar fields. So we get about, we're about 15% on an annual basis from hydro. And, and that tends to compliment the solar somewhat. Well, when it's raining. It's not Sunny, and vice versa. And then the rest and
Robert Bryce 21:12
those hydro, just to be clear. And so are these what they call them run upstream or run a river
Brad Rockwell 21:18
on a river. Exactly.
Robert Bryce 21:20
They're not impoundments there's no dam there that No, I mean, or Okay, go
Brad Rockwell 21:25
ahead. Yeah, yeah, yep. Just small little diversions that take some water from the streams, and then put it back in the stream down later on. I see. Yeah. And then. And then solar, we have, I mean, too many to really run through, but I'll just kind of break it into thirds. So about a third, we have over 100 megawatts nameplate solar installed on our system. Like I told you, I mean, midday, we're about 50 to 60 megawatts of demand. So how do we do that we have more solar capacity than we have demand? Well, a third of that is rooftop solar from customers. So roughly 33 megawatts of rooftop solar. And when you look around at the roof, you know, people install this stuff in all different forms and fashions. Sometimes it's on a north facing rougher, you know, it's overgrown with things and people aren't managing it so well. So you know, we're not getting the full output of those, but that our customers have that choice to put solar on, on the roof. And I'm happy to get into that if you want later. But another third of that solar capacity, about 32 megawatts is central station, large, you know, utility scale solar projects without storage. So those are the ones that really move frequency around, you know, in Hawaii or solar resources, not like the desert southwest of the continent. It's it's typically partly cloudy over here. So we always have passing clouds, and solar production is moving around all day long. And so we have to deal with that variability. And then the last third is the ones that have enough storage to essentially store all that solar production during the day and then shift it to nighttime or to firm it up. And those are the ones those solar and storage with the synchronous condenser are what enabled us to run the grid at 100%, you know, during the day, and we've like I said, we've gone for as long as nine hours in any one day, but I mean, almost every day, we're doing at least a few hours of 100%. Renewable.
Robert Bryce 23:29
And so what does that mean in terms of costs for your customers? What is what is your average kilowatt hour price? And do you have time of day pricing?
Brad Rockwell 23:38
We don't we have just one rate 24 seven, we've done some pilots with timing use, but we haven't really seen the value of it yet. But our rates this month is I believe it's 33 cents a kilowatt hour. And so it's been it used to fluctuate wildly. I mean that To give you an example, in the 2008 oil spike and went to 49 cents per kilowatt hour and six months later, it was down to 22 cents. Wow. And so you know how to businesses and residents plan for that type of energy bill. And it's very hard. So the success of all this renewable penetration going from 8% renewable in 2010 to over 60%. Today has been that all these renewables are fixed price, you know, fixed price for the whole term. So our our range of our electric prices now are very tight. So yeah, they're still higher than most people would like. I think anyone living anywhere on this earth will tell you they're paying too much for power, but but it's very stable now and people can actually plan
Robert Bryce 24:44
that 33 cents per kilowatt hour. Just to put that in perspective, the average residential rate in the US about 12 cents has been climbing slowly but but that's so one of the reasons Am I put it in the form of Question one of the reasons that solar and storage work were on for the coil and utility cooperative is that your alternative is diesel fuel. And so you've, you have a high price, your your, your your price benchmark is pretty high. That that, that the the system that you're operating wouldn't necessarily work somewhere else, because of the higher cost of those systems. Is that is that accurate? Yeah,
Brad Rockwell 25:27
yeah. I mean, I mean, we are clearly, you know, want to do good and to create, you know, use clean energy sources. But there's, I mean, we'd be lying, if we didn't say there's a financial component, we wouldn't be doing this, if it was going to cost our members, our ratepayers a lot more money. The nice thing about our renewable push here in Hawaii has been this has actually saved our members money by adding all these renewables, you know, as compared to what oil costs are. But yeah, we're using a transportation fuel diesel, in units that are not as efficient as because of economies of scale, and they're small size, you know, we can't do 1000 megawatts combined cycle, each class, you know, 60%, efficient gas turbine over here, it's just not going to happen. So we have relatively less efficiency because of that. So it translates to high power cost.
Robert Bryce 26:22
And you you say that, that big unit, because in general, as I understand it, and correct me if I'm wrong, in general, historically, in the power business, the bigger your power plant, the more efficient it is, if there was just an inherent benefit to having a larger system, that you get the benefit of that size. But is that still true today? Because as I look around, and and and have a look at recent developments in Mexico and California, it seems like the average size generation unit has gotten smaller, substantially so right, that we're not building necessarily 1000 megawatt generators very much anymore. Instead, it's 4050 100 megawatts, 200 megawatts? How do you see that? Right?
Brad Rockwell 27:06
Yeah, I mean, the efficiency is still better with the larger units, no doubt. I mean, you know, and when you look at the cost to build a power plant, you know, you've got interconnection, you've got the construction got the civil work, you got, you know, all the equipment and things like that. And so clearly if you can, and a lot of those costs are the same whether it's 1000 megawatt plant or a 500 megawatt plant, right. So clearly, you're going to get more efficiency if you go larger, but I think probably what, what you'll find is that there's this push to be more distributed, so that that's where the smaller sizes have a place. And, and in the best interconnection sites, you always have to look at how you're going to tie into the grid, you can't just cite a power plant anywhere. So some of those interconnection requirements may restrict going to a larger size, that you may only be able to incorporate, you know, 100 megawatt turbine or something like that.
Robert Bryce 28:03
Because you don't, because you don't have the transmission capacity.
Brad Rockwell 28:06
Correct. And the cost to, you know, build that with is cost prohibitive, or something so, but but I think, you know, I mean, clearly, if you could just, you know, do a number of large plants, it's going to be more efficient, but, but again, then, you know, maybe those larger plants have to be out in the middle of nowhere. And to transmit the power, you've got more losses. So you can do smaller ones closer to the load center. So you know, the efficiency I was talking about is at the plant level, not necessarily delivered to the customer, which has to be taken into account.
Robert Bryce 28:37
Right? So you may have a higher capital and operating costs for a smaller generation unit, but it doesn't necessarily mean that it's more expensive, because of the other issues that involving transmission and the other other factors is that. Okay, so, um, so then let's zoom out, I want to zoom out and talk then, because we've gone over, you only, you know, your your cooperative is I'm just looking at the numbers here of 139 employees, as you said, 37,000 meters 3000 commercial members. So it's your, your operating your own grid, you've got here, essentially your own regional transmission operator, you have this very unique system that is constrained, and you're able to run it on high penetration renewables. But then I want to look at first look at Hawaii and the challenges there and whether you think they can get 100% renewables by 2045 and then zoom out to the US and and some of the issues that we talked about offline about land use conflicts, because that's the other part where you said even on your island, you didn't have landowners that were willing to to put up with wind turbines or put install wind turbines. What's happening in the other islands. I know that there's been a lot of controversy I've written about it on the island of Oahu, near kahuku with the wind projects there, and there's also been controversy over the wind projects. In Hawaii because of concerns about and in fact, the mortality problem with birds and bats. So how do you see the? Here's the question how, what is it? What is Hawaii going to have to do to meet that renewable mandate by 2045? And can they do it?
Brad Rockwell 30:18
Yeah, I think the, you know, short answer is yes, we can do it. Every Island. And every place, every grid is a different set of circumstances. So you know, here on it, I feel very confident we can do it. We are a more world. So we have a lot of unused open land to develop more and more solar and storage projects. So we can, you know, we're talking one or two more large solar and storage projects, we're now in the 90%. And the key is, we can't give up any of those conventional units, because, you know, we're going to have so many eggs in the solar basket, when we have cloudy days, you know, we're going to need a lot more storage than battery technology can currently do so. So we're working on a pumped hydro storage project combined with solar to get us a little bit longer duration, 12 hour type storage instead of four or five. And, but ultimately, to get that last five or 10%, we probably use biodiesel, right. So it's, you know, it's a higher cost fuel, even then our diesel we're running now, but if it's only five to 10% of your mix, it doesn't impact the rate a whole lot. And it allows you the confidence to say, okay, when I get a week of clouds, I can run this biofuel, you know, biodiesel in my conventional units, all my units can run biodiesel, essentially. So that's the easy button. Unless, yeah, and
Robert Bryce 31:42
if I can interrupt there, because that's an important point, which Scylla has recently put forward. You mentioned word Scylla. Before the Danish company, I talked to one of their people fairly recently. And they're they put forward a plan for renewables in California, but it retains the combustion engine that that that combustion, you know, there's a big push to get rid of combustion and transportation and so on. But what I'm hearing over and over and I just heard you say it is that actually, if batteries will work for a few hours, but if you have more than a few hours, then you're going to need combustion, because you it's it can it can provide that security of supply better than batteries. Is that a fair way to put it?
Brad Rockwell 32:26
I wouldn't say combustion is the key. It's it's the storage essentially. So whether you're talking battery storage, or whether you're talking a tank of fuel, okay, that can last you for days. Yeah, I see. That's the key right? I don't care what that fuel is. Maybe battery technology gets there. Maybe we can do a larger pump title. But if I got a fuel tank that lasts me a week, that's a heck of a lot batteries and better than a battery that lasts four or five hours,
Robert Bryce 32:54
right? I see. Yeah. And and the density of that fuel in the tank that that yellow is far
Brad Rockwell 33:00
liquid fuel energy density is just unbelievably You know, that's that's just energy, the amount of bt use per per volume in liquid fuels is it just can't be matched by anything right now.
Robert Bryce 33:15
Right? Yeah, and that's why one of the reasons why it's so dominant transportation is that it's just it's nearly miraculous, right? The energy density of diesel fuel and gasoline is it's what is it 13,000 BTS per kilogram, something like that I'm trying to remember as
Brad Rockwell 33:32
always, I know it in beacuse per gallon, because that's what use but it's uh, you know, it's about anywhere between 125 and 135,000 views per gallon. You know, even hydrogen is less than that on a volumetric basis, a lot more on a mass basis. But, you know, if you're going to try and switch the hydrogen, you got to compress it to get it down to fit in a tight space still.
Robert Bryce 33:54
Well, let's stop there for a second because hydrogen now is all the rage. And and, in fact, I was talking to a friend of mine in Washington, who's in the natural gas business. And while I was asking him about his views on hydrogen, what are your views? You've worked in this business for a long time? And, you know, what the what, how grids work and how systems work? Is the hydrogen economy coming into what extent is it? How much do you believe in it?
Brad Rockwell 34:19
Yeah, I mean, I stay. You know, I keep my ears open for it. But it still seems like it's a it's a little further away. I kind of see it, it could essentially be an option for biodiesel, right. So we get to 100%, renewable, I talked about how we're going to need some biodiesel. But ultimately, we can run some of our combustion turbines on hydrogen. I mean, there's some work going on now with 30% hydrogen, and they're trying to get that up to 100% hydrogen running in combustion turbines and so that may be the next step beyond if the price point comes in in the technology. gets there, but I don't see that as any anywhere in the foreseeable future for us, you know, over here we're going to have because we don't have natural gas to reform and make hydrogen, so it's going to have to be electrolysis, you know, maybe with otherwise curtailed solar energy. And I just were, and one hand, I feel really blessed living in a place like this, where we are the ISO where the RTO, where the utility, or the IPP is, we developed an own renewables, and we've got conventional, I get to see everything all at once. It's an amazing laboratory to do this stuff. But at the same time, I kind of always say, We're too small for science projects, I can't waste my time on hydrogen electrolysis you know, until there's someone like a Siemens or a GE, or you know, somebody that's gonna back this thing, and it's proven, then, okay, we can bring it over here. But we don't really do pilot projects and science projects. We just don't I don't have the personnel that deal with that stuff. We have to focus on doing things that are real in here now.
Robert Bryce 36:05
Yeah. Well, is it fair to say, as you said, that I just popped in my head? Well, you know, we're not going to do science projects. And partly that's due to just your size, right, but you're not, you know, your, your, your, your consumption rates are far lower than than the average consumer in the in the continental US. So it's, it's another part of the uniqueness of your system, your your system, compared to, and I've been to Iceland, and you know, you don't have geothermal there, right, you have so hydro, but geothermal 5% of their mix. So anyway, so you said that you thought that back to the State of Hawaii, you think that the state could get there. But if I'm looking at what happened in kahuku, you know, to what extent is that all renewable mix, going to be split between solar and wind? Do you think it's gonna be more? Yeah, or solar? Well, how do you look Well, for me?
Brad Rockwell 36:53
So yeah, I hadn't really gotten to the rest of the state I was talking about here on Kauai, we can get there. Now. I think Maui and the Big Island are similar to Kauai and that they're still very rural. And there are, you know, lots of open space, they have more demands. So it'll look a little more challenging, but especially on Hawaii, on the Big Island. They have geothermal. So the only island that has geothermal, I mean, it's still that island still growing from lava flows. They have they've done wind, you know, clearly, they can do a lot of solar, they have hydro there. So they've got sort of a wealth of renewable resources over there. I think that's very possible. And they've always been a leader in renewables. Maui too, I think. But when you get to a wahoo, that's the real problem. I mean, you've got an island that's almost the same size as us here. But it's, you know, got close to a million people in it. And so it's, it's more urban, a lot of the island sea don't have the open spaces. As you know, we talked about energy density, renewables are really weak in that area, they require a lot of land. And as we're finding out over the last couple years, people don't necessarily want these renewables right in their neighborhood, you know, especially the wind turbines. And there was a fight last year where he was putting in some wind turbines on the North Shore of Oahu, it kahuku I guess, apparently, up close to a neighborhood. And, and, folks there, were saying, Well, why do we have to look at these things? You know, these are 568 foot tall winter bins, you know, in a place like Hawaii, we'd rather look at the beautiful mountains, and you know, what are we getting for this? Right? Why do we have to look at it. So there's a push while that that plant ended up that thinks it's completed construction, it may be generating power now, it's ultimately went through but you know, there's still some pending litigation and things. So
Robert Bryce 38:49
as I recall, those the the neighbors are still fighting it. And there were 200 people arrested in the protests, and that was November of 2019. So it was remarkable to see and I saw the photos in the Honolulu star advertiser, I've never seen civil disobedience to that scale involving renewables. And to me, it was just another example of these issues of land use conflicts. So right, and then you mentioned that yourself. So so the Hawaii Maui, but you think that the Allahu then of the islands will have the most difficult time meeting that renewable mandate? Is it possible that other islands would then cable over some of the power to to a wall? Who is that
Unknown Speaker 39:34
even though I don't, I don't I don't
Robert Bryce 39:36
know my geography and well know, what those distances are.
Brad Rockwell 39:40
I mean, it's a great idea. And actually, it was an idea that was floated around a few years ago. And there was some work done on it. And you know, at first glance, you think, yeah, makes sense, right, a wahoo. I mean, clearly us on the nape what we call the neighbor islands can exist with the quality of life we have without the hub Honolulu, Honolulu airport, the port, you know, that's where everything that comes to Hawaii comes essentially through Honolulu, you know, via large ships, puts gets put on smaller barges and comes here. So we benefit from Honolulu having all that infrastructure. So, you know, you could make a case to say, Well, why shouldn't you know, kawhi has extra open land even after we've gone to 100% renewable, why shouldn't we build out more renewables and send that excess power up to Honolulu, and clearly it'd be good for us as a company to be able to sell them power. But there's a real resistance for folks that live in a rural area to overbuild renewables that are already sensitive to power the big city and I think you'll see that anywhere. I mean, I think if you look at any sort of undersea cable, it's always been the opposite where you're going from a large population or you know, a place that has a lot of energy infrastructure already sending it to a small island or, you know, that doesn't make sense to build a power plant. They're not the opposite.
Robert Bryce 41:06
Well, I think that's a that's a key point because I see that happening over and over. In fact, all across the US you had San Bernardino County, California, the largest county by area in America last year said no more hi large scale renewable projects. This county is the home of Ivan Pon Abengoa Mojave, they can't build Thurman's thermal solar there can't build wind, and generally can't build much new wind capacity in California at all. And you see the same kinds of conflicts on in New York for onshore wind. So I think it is exactly as you said, I think it's it's very much the urban rural divide, and I don't see any cure for that. I think that that's a it's a it's very much about people concerned about their own neighborhoods.
Brad Rockwell 41:49
Yeah, no, I get it. Um, nobody wants a power plant next to him. I understand that. And that's, I think solar is probably the most palatable because it doesn't mess up your view plane, it doesn't make noise, it's no rotating, no moving parts. Right. Species impacts are limited. So if people are against even solar, then wow, you know, I, I think, you know, look forward to more nuclear plants, which, you know, hopefully, because, you know, why not build more nuclear, then in that case, it's the one that doesn't emit any greenhouse gases. And as I heard on your podcast the other day, I thought it was a great point is all the waste is contained? You know where it is? So you're not emitting stuff into the atmosphere? Yeah, that that waste has a lot of, you know, some people have concerned about it. But it seems like, and just the solution of people aren't willing to deal with large scale renewables and they don't want to see them then. Okay, build the nuke plant mountain palo verde away from everyone and send the power to the city.
Robert Bryce 42:56
Yeah. Well, it's interesting, you mentioned that about the solar because I'm in agreement, the, the, the, one of the great virtues of solar is that the solar resource can be closer to the consumer, right. So you don't necessarily need the high voltage trend as much high voltage transmission capacity, but you also have, it has power density, 10 times out of wind, so you know, about 10 watts per meter. But, um, so we've covered kawhi, we've covered Hawaii kind of more generally, then so. And by the way, I need to make my identification, you're listening to the power hungry podcast, my guest is Brad Rockwell, the executive manager of the CO Island, executive manager of operations. At the quiet and utility cooperative, you can learn more about them at K Iuc. Co Op. That's k Iuc. Co Op. So, Brad, let's talk about these issues more broadly than in the US. You said you're very much all of the above. strategy. Why is it then that the idea of 100% renewables has become so politically popular, because that is the way I see it, that there's a very large and powerful group of people are saying, well, this is the only way it should all be wind and solar. Why is why do you think that that's that that idea is so politically popular?
Brad Rockwell 44:17
Well, I think it's because it sounds good, and most people that are most people in this in, in this world don't have to operate grids, and so they don't have to deal and be responsible for the challenges of some of these decisions. Right. And so I get to see it all and, you know, clearly I'm an advocate for renewables, but there's a place for other options as well. And we have to think clearly, first and foremost, we have to make sure we deliver safe and reliable power and affordable price. And when you start saying how, what you can do to do that what you can't, it's difficult, especially when you start looking at The fact that each area is different, each area has different resources. You know, southeastern part of the country doesn't have a lot of wind resources, you know, other places have more solar resources. And, you know, what are you going to do in the northern part of that country? I mean, it's just, it's just a broad statement to say, 100% of the way to go on site? Well, no, I think we need to continue to be cleaner, and to continue to do things at large scale, because it's more efficient, and to work on other aspects of our energy issue, like transportation and things like that, you know, building efficiency when you can and stuff but bottom line, I think it's just it sounds good. And most people aren't really tuned in with the real challenges of running the grid.
Robert Bryce 45:48
And is that because I mean, I mean, it's one of the things that seems to me is so unique about the electricity sector, right, that people understand oil better, I think, than any other form of energy, because they a lot of people pump their own gas. And so they have an idea of what it costs how long it takes to fuel the car, they can smell it, they you know, they don't touch it, generally. But it's more tactile to them, it makes more it has more resonance to them in terms of the physical ness of it. Where's the grid? It's just like, well, I plug in, and therefore, why can't it all be renewable? And to back to the renewable or the rural urban thing? It's just oh, well, we'll put that stuff out there. Somewhere in someone else's neighborhood. Yeah. But don't put it in my neighborhood. Right. Yeah. That that. And it sounds like, all of these issues are ones that you're seeing, even in this little microcosm there and your own your own grid. And in terms of those challenges is how do you see it?
Brad Rockwell 46:48
Yeah, no, that's, that's true. And I think what I think of also is how, you know, I think a lot of people, some people can afford to put solar on the roof. I mean, I have it on mine, I don't have a battery at my home, but I have solar and a lot of people that can do that are tend to be wealthier, more savvy about energy and things like that. And they just think, Well, you know, everyone could just put it on the roof. And then you know, we don't need power plants and things like that, we'll just all be so distributed, and, and there'll be this new energy economy. But if if putting solar on your roof makes more sense and kawhia than just about anywhere else, because of our heart rate, high rates. And, and to this day, only 13% of our customers have solar on the roof. So
Robert Bryce 47:41
in most of the coal and the co op doesn't help it doesn't subsidize that at all are there do you
Brad Rockwell 47:45
we don't provide a rebate, there's a pretty lucrative, you know, there's still the federal tax incentive, and there's a pretty lucrative state tax incentive. So it's, it's, I mean, that's how it's subsidized. But most of those people, when they go to put solar on, they want to, they don't want to just reduce their midday demand, they want to actually over build the system to try and get to a zero bill each month, right? So they want to send me a bunch of excess power during the midday when I told you, I'm already 100%, no, I don't need it, that's, I can't really pay you for it. Even still, if I say I can't pay you for it, they still want to just give it to me, they want their system over built. So So these people now are not really contributing to the to the price, the cost of the grid. Now, all that burden shifted to the other 87% that don't have this, that maybe they're renters or their their home, you know, isn't suited for it, or they just don't have the money to put in a 10 or 2030 $40,000 system. And people will say, well, that's where community solar comes in. And we're doing some community solar projects. But still, this is a you know, that, that the grid is amazing thing. And it allows people who have renewables on the roof, this huge, essentially huge storage device. That's going to be there. When your system isn't producing even your battery, even if you have one or two power walls, you know, you still going to need the grid for some times. You know, to size a battery at your home, you'd need you know, to basically tell the utility, take your line off my house, you would have to figure out the ultimate most power you're going to use, you know, you're throwing a Super Bowl party and it's February and there's no sun. And you know, that's how you got to size your storage. Right, right. Unless you don't want to be able to watch the fourth quarter of the game or something. So right. That's a huge battery. That's much more than one power wall.
Robert Bryce 49:49
I'm just I'm just having a little trouble on the audio here. Are you Can you hear me now still? Yeah,
Unknown Speaker 49:55
I hear you.
Robert Bryce 49:56
Yeah. Okay. Well, let's jump back to that idea on the solar because that's One of the things that I think is really important to keep in mind is that the the, the people who have solar and I have solar panels on the roof of my house and I got three different subsidies right I got the investment tax credit federal investment tax credit, the Austin utility Austin energy paid an amount of six or $7,000. And then Austin energy was also giving me a very lucrative payments for my the electricity I produce, which is about a one megawatt hour a month. So I was getting three different subsidies. But you mentioned that issue of the equity then it can you follow that up again, a little bit? So are the people you said 13% have solar on their roof? Or the 87%, then effectively subsidizing the 13%? Tell me how that works?
Brad Rockwell 50:48
Yeah, so you know that 13% that have solar on the roof. So it's broken up in there's a small amounts that are Nam, you know, those, those people are clearly being subsidized by the rest of us, because Nam dam is a straight net energy metering, sorry, it's straight retail for retail, right? That's a relatively small amount, most of our customers are with their solar system, and then they're actually selling the excess to us at our avoided cost rate. Which is, unfortunately, tied to the price of oil. So we're paying for excess solar, based on the current month's cost of oil. Hmm. Which is something we're trying to get resolved. But but we're fully regulated utility, so things take time. And so so those people that can afford to put these systems in, are doing fine there. But you know, they're they're paying relatively less than their fair share, to continue to operate the grid and to be able to have this amazing resource, they're still tied to for when a cloudy day comes or their battery doesn't have enough storage and, and whatnot. The rest of us are paying. So there's there's I mean, it's just a very, very nuanced issue. But there's a definitely a social justice aspect of, of installing rooftop solar. Yeah. And
Robert Bryce 52:21
I like the way you put that, that they are paying relatively less than their fair share. And that is something that we've seen in California and California, public Advocate's offices made this very point that because people are putting on more rooftop solar than the utilities are selling fewer watt hours, well, so then their existing costs have to be spread over fewer watt hours, which means every one hour just gets a little bit more expensive. So that's the dynamic we're talking about. Is that not right?
Brad Rockwell 52:52
Yeah, that's the dynamic. And I would also add that in here, I think it's anywhere but especially here. The cost that I can do a central station solar plant for compared to what I can put it on my house, and I know this because I just did it, central stations about one fourth the cost of installing it on my house. So if you think about, well, if we're going to just do it with everyone's rooftop, the amount of capital that's involved is going to be four times more than doing it with Central Station. And so and and but yet the numbers still work for these individual ratepayers. How does that because the subsidies and things like that, so ultimately, we're all we're all paying through it for taxes and things, we're subsidizing this very capital intensive method to allow people to have the option to do it. And to cut back on their demand, I think there's a place for it, it's just, you know, if I could sort of go back in time, I'd say, look, we've only got X number of rooftops on the island. My midday demand is why. So I, you know, you can't over build the systems and and sort of juice your economics, if you will.
Robert Bryce 54:03
Because and I think that that's a key point, and you've made it you've referred to it before, which is that, yeah, you can run 100% renewables for some hours. But then you always have to have the available generation capacity for when that renewable source isn't available. And that that is the goes back to the capital requirements, right that you've got to the issue. For almost all of its history, the electric grid has operated on this idea, we're only going to build as much capacity as we need and no more. But now, correct me if I'm wrong, the challenge with renewables is that you have to over build the grid and then there invest more therefore invest more capital to have the system available for when the ready to kick in when the renewables aren't available. So it may be twice the size of what would in an optimal historical census is what may need twice as much pasty as you would historically is that am I overstating it?
Brad Rockwell 55:03
I think it's fair. I don't know if it's twice as much. I mean, what we've our view here has been, we're not going to retire any of our conventional capacity while we add renewables. So clearly, you know, I mean, we could have met the demand with without ABS renewables by just burning a lot of fuel in our conventional units. Now, we're adding renewables, it cuts down on our fuel costs, but we still have to maintain this capacity, because the days occur every now and then when there's no sun here, or you know, the hydro is not performing or the biomass plants down. And people won't stand for days have no power. So we have to maintain that capacity. So yeah, it is. If there's going to be more resources, that's not necessarily a bad thing. I think it's good to have more capacity. But it is hopefully beneficial from an economic standpoint, because the renewables you're adding are very cost competitive.
Robert Bryce 55:58
Right. Right. And you don't have and the other thing that is unique about your system is that it's relatively small. So I mean, in terms of your, you know, you have, what, 1400 miles of high voltage transmission, which, you know, you're 500 square miles, 562 square miles, I mean, you're not having to build high voltage transmission to meet your needs for renewables. Is that is that true?
Brad Rockwell 56:22
Yeah, yeah. Because our grid is, I mean, our island is almost a circle. And our grid is, you know, our transmission system goes around the island already with nicely. It's not like we have, you know, some sort of back corner of the island where there's no part of the transmission system or the grid that we're going to develop renewables, and we have to build a long interconnection, it's, you know, essentially, it's not too far to tap into the existing transmission or substations whenever we build a new renewable resource.
Robert Bryce 56:51
Gotcha. Okay. Well, Brad, this has been great. I mean, it's been a, you know, we had some challenges earlier on, when we talked, but I'm glad that we could talk about these things. If I'm missing something that we aren't, we need to discuss it either. Regarding Hawaii and the limits there any other things that you want to discuss?
Brad Rockwell 57:13
I mean, I think that, you know, I know you always like to do a call to action, and for me is, is maybe just a utility guy. I mean, I'm not trying to sell anything, are just trying to talk about the challenges and things. And I think, you know, everyone, I think most people will agree that we want to do more renewables, and there'll be varying levels of, you know, whether that's possible, or whether it makes sense or not, but in order to do that, it's gonna require a lot of support. I mean, we've seen we talked about it here today that even large scale renewable projects are getting some resistance. And, and so people need to figure out what they can get behind what they can support instead of focusing on what they don't and protesting against things. You know, if you've got an issue with something, get involved, open the dialog, figure out what is it about that thing you don't like and figure out how you can solve that issue and maybe get behind it. Because the fact is, it's a physics issue. renewables are not very energy intensive, or not very energy dense, they're going to take up a lot of space, they're going to be in everyone's neighborhood, not just kahuku, on a wahoo, they're going to be and you know, not just in Puna, on the Big Island, they're going to be all over the place. And so if we're going to really get to 100% renewables, so we're going to have to figure out how to get comfortable with these things. Because the days of, you know, generating power in the middle of the desert and sending the power to the large cities or generating power in one corner of the island and sending it around. It seems like those days are gone, because people don't want those types of power plants anymore.
Robert Bryce 59:02
And that's, and that's about the sensitivity of people in their, in their regions about their neighborhoods that their people care about that is that I'm just responding to what you said is that I'm paraphrasing, he said, Is that fair?
Brad Rockwell 59:14
Yeah, I mean, you know, nobody wants to look live near a power plant. I don't care what kind it is, and live near power lines. But we all want that power. And we all are using more and more of it. And electrification is only going to make that increases his transportation, other parts of our daily lives. Switch over to electricity. So these things are coming to a head.
Robert Bryce 59:42
Are you Well, I'm glad you brought that up. So are you seeing any electric vehicles on Hawaii? And if you are, have you done any projections on what that might mean for your load?
Brad Rockwell 59:51
Yeah, we are. It's a relatively slow rate. We've got a few You know, I think the last two months we had seven new you registrations each month. So we've got a few 100 here on the island, that's compared to 70,000 registered vehicles total. So it's still a very small amount. And we have done some analysis. You know, luckily, this huge amount of storage we've added with these PV farms, suit us quite well for that for meeting any sort of increased peak. Right? I can I can handle a peak that's way more than what we're dealing with just because of the storage and I can do it for hours. Right. So that, you know, solar and storage coupled very well with the coming electrification.
Robert Bryce 1:00:43
electrification of transportation, right? Sure. Yeah. Yeah. Okay. Good. Well, I think that's a good spot to end. My guest is Brad Rockwell, the executive manager of operations at the CO Island utility cooperative, Brad, I'm really pleased we're able to do this and I appreciate your your patience on finally getting it, getting it right. We had a few stumbles in making it happen. And thanks to all of you for listening to the power hungry podcast, if you like it, give us a positive rating on your favorite platform, iTunes or Apple, Apple podcasts or Spotify or wherever you're listening. And be sure to tune in again. So Brad Rockwell Many thanks again for being with us. And, and to all of you out there. We'll talk to you again on the next our See you again, I hope on the next podcast edition of the power hungry podcast.