Let's take a look at some of the technologies and ideas, and approaches within the broad topic of wind. One particularly interesting aspect or type of wind we're thinking about or recognizing is offshore wind. Wind power overall can be put in two types, onshore and offshore. Offshores is out to sea, out in the lake, whatever, over water. Right now offshore accounts for a relatively small piece of the total wind pie, probably about five percent, depending on this data you look at. But it's growing rapidly as just wind overall and is shown in this plot. Global offshore wind has grown quite quickly from trivially small back to say 2010, to a significant 27 gigawatts by 2019, varies by country. But much of that you can see is here in China, in Germany. Record capacity additions in 2019, the most recent good data we have, and you can compare that a bit with wind overall, which is installing about 60 gigawatts per year. From a percentage perspective, offshore wind is accounting for a growing piece of the overall new wind pie. Forecasts, short-term forecasts for offshore wind showed continuing to show very rapid growth, and these are fairly reliable forecasts because these are based on announced projects. Now, realistically, not all these will be built, but probably, a large percentage of them will. This is not a look at the market thinking, forecasting historical trends, but a more data-based approach where we're looking at actual projects that had been announced. Now again, not all announced projects are built, but in these cases, a lot of these projects are pretty far along and I expect most of them will in fact be built. You can see continued rapid growth in offshore. Now, within offshore, keep in mind there's wind overall onshore and offshore. Within offshore there's a new approach which is very promising and worth spent talking a little bit about called floating offshore. Let's talk about offshore wind for a minute. Putting your wind turbine out on the water, typically out in sea, but it could be out in the lake has several advantages. The wind resource is better. Have you ever been out in a boat, and you see how the wind picks up as soon as you get away from shore, because trees and buildings and grass and bushes, all that interrupts the airflow. But you don't obviously have those interruptions when you're out on the water. Waves do the same effect, but they tend to be smaller than trees and buildings generally. If you go out offshore you have better wind resource. It's easier to move large pieces of equipment, so just humongous turbines by ship than on land. There are disadvantages of going offshore as well. You have to run cables. The costs are higher, for various reasons partly related to some more complicated installation. But one of the technical challenges with offshore is, in the past, offshore wind turbines have to be rooted in the ground under the water. You'll sink pilings underwater and put in concrete rebar, whatever's necessary to securely anchor that wind farm. Once the water gets beyond typically 20 to 30 meters, it's really no longer practical to build an underwater structure. It just gets prohibitively expensive. Offshore has been constrained to areas where the water depth is typically no more than 20 to 30 meters, and that's just giving them constraint. It puts a lot of offshore areas out of play, but that is changing due to new technology of floating. When floating platforms. The idea is wind turbines don't have to be anchored in the seabed, they can be tied to the seabed via a chain, a link so they don't float away, but they can move with the water. That makes it possible to use vast new areas that have deeper water for offshore wind. Now, this is a new approach, a new concept, but there's only a handful of floating offshore wind farms installed. But early results seem to be that they're working. There's a lot of proposals and interests in new floating offshore wind. Definitely, a technology to watch. If offshore floating platforms work and are technically reliable and cost-effective, vast new areas of the globe will be available for offshore wind installations. Stepping back and talking about offshore overall, including floating and regular, the forecasts show continued rapid growth through 2030, these are different consulting firms that look at these data, but we will see more and more growth for offshore wind. This growth will accelerate if floating platforms take off. Offshore looks to be a very promising approach. Let's talk about other technologies related to wind. There's increasing interest in what are called hybrid wind projects. Data on this are early and spotty, assume showing only US data here. But the idea is one of the challenges of wind is variability and output. If you have a wind turbine or a wind farm, the wind can be stronger or weaker, so the output of a turbine or a wind farm entirely will go up and down with the wind. That makes it all else equal or less valuable resource than it would be if it was, say a dispatchable power plant you could turn up and down as needed. Well, one solution to that is to make a hybrid wind. You combine wind with storage, with batteries, for example. You combine wind with solar PV, solar photo tech, because the wind and the sun tend to not move the same way. So if you combine output of wind and solar PV, you'll get generally less fluctuations, you can call it a flatter or less fluctuating output of the combined wind farm. There's more and more interest in hybrid wind projects. There are only a handful in the US, as you can see here, but it's an interesting new approach that may take off. My expectation here is that we'll see wind combined with storage with more and more projects because if you have a wind farm and you could combine it with storage, then you can essentially sell your output as in some ways more reliable or dispatchable than if it was only wind. Another wind approach on a different path is what's called small wind. Almost all the discussion ones is about wind power. In the literature and research is about big wind, utility scale wind, turbines that are 2-10 megawatts or even larger, we'll talk about in just a minute. How about about small wind? How about the wind equivalent of a rooftop solar PV system? Well, not really happening. That technology has not taken off, has not achieved significant market penetration. There's some data in the US showing domestic sales and imports. As you can see, they've pretty much faded away to five or less megawatts per year, which is really small. That's the US story. Global story is similar. There are niche markets, so this makes sense, mostly off-grid applications. But small wind has just not taken off the way big wind has. In the US, there have been reasonable policy support for small wind, but that industry has just not really taken off the same way big wind has. Why? Well, costs essentially. It's very interesting. If you go back to 2010, the cost of small wind, that's 100 kW, and PV were about the same. We'll talk about PV shortly. Well, since then, PV has dropped dramatically over 50 percent. Small wind has actually gone up a little bit, cost per kW. That technology has just been left behind in essence by other one, particularly rooftop PV. If someone's thinking about a small power system for a house or a small community, PV is, by these data, 60 percent less expensive in terms of installed cost. Small wind has just not really found its footing. Another new technology, a new approach for wind would be big turbines. Turbines that is the size of wind power plants or powered systems has continued to grow over the last 20 years. It's not clear if there's an end to this. For example, the average size of a new turbine in the US in 2019 was 2.6 gigawatts, for a new offshore was 6.3. That's what the averages are. But the newest turbines just coming out, and this is a prototype in fact, but they're probably looks to be contracts being signed for this. Is a mass of 13 megawatts. You can see the significant gap where the newest turbine just coming out is more than double the size of the average one going in offshore. Long way of saying turbines are getting enormous. To summarize where wind is going, there are some technologies to watch. One we didn't talk about, but I'll mention quickly is repowering. The turbines themselves have improved so much over the years, mostly well due to several lots of engineering improvements. One that's very noticeable, because they've gotten a lot larger. There's a growing market for repowering. Taking existing wind farm where everything's working fine, but where the economics are such that it makes sense to just take those old turbines down and put up new ones because the new ones produce so much more electricity. There's a vibrant repowering market. Replacing old turbines, not because they're not working, but because they're in some ways technologically outdated. We're talking about floating platforms for offshore wind, where if they develop and find their footing and essence, well, become more popular they'll open up large new areas for offshore wind. Turbine size, where the latest announced turbines are 13 megawatts, more than double the average new installed offshore turbine. Is there a limit to this? Can we make 13 megawatts work? Worth watching that. Finally, hybrid plants mixing wind probably with storage, possibly PV, and insuring smoother output of the combined plan. All technologies to watch. Now, there are different perspectives on where wind is going. One somewhat surprising forecast or scenario that is worth taking note to look at we talked about this earlier, is the one for the US, which is essentially a business, as usual, assuming no large technological or policy change. This forecast shows wind fading away, where most new power plants mostly post-2030, are solar, and it says oil and gas, but it means gas. Why that's the case? I don't know, but there's at least a little bit of a question about wind's future. Will it be able to compete with solar and natural gas? My view on this, it's already competing financially with natural gas. But if natural gas prices drop, that may change. It may be the case that soap this forecasts, or I'll call it a scenario, [inaudible] getting so inexpensive to the extent there's interest renewables, it's based on wind? I don't know why they see this happening, but there's at least one question about winds' future ability to compete with solar. Just to finish up our wind piece here, what are some of the issues that affect wind's future? Cost reductions. As I pointed out, wind is not yet a mature technology. There's definite potential for cost reduction. I just want to mention a few of these here. What does it compete against? If natural gas partners stay where they are, wind is competitive. If natural gas gets much cheaper, it may not be. Finally, I want to mention cost of solar energy because that's one of the major questions about wind and solar PV. They already dominate new construction. As I've noted earlier in the course, 75 percent of new power plants built today are renewable. Most of that is wind and solar PV. But which one will see greater cost reduction? Because, at some point, wind and solar PV will probably compete, and they probably do already in some markets. Who's going to win? I don't know, we'll see. That's a sense of where wind is going. Next, we'll look at where solar PV seems to be going.
