Wildman Energy Blog

Solar Panel Operating Temperature? Call in the Boffins

It may be possible to drive up solar PV plant output with better panel heat dissipation, but a better thermal model is necessary first.

A great way to reduce the cost of solar power is to increase the output of the solar plant. Solar photovoltaic (PV) panels lose efficiency when they operate at higher temperatures, and unfortunately, they generate heat and operate well above ambient temperature. So, a potential opportunity to boost power plant output is to dissipate heat better to drive up efficiency. After recently seeing a not-uncommon 7% thermal loss in a PVsyst simulation, my intention was to write about the value proposition for better panel heat transfer. However, it seems that panel thermal behavior in an operating plant is not very well understood. What seems to be needed first is further scientific study to understand what governs panel temperature in real solar plants. Then, a clear assessment could be made for the potential to boost output from better heat dissipation. Before the design engineers get to work, perhaps the boffins should have another go at it.

Reducing the Cost of Solar Power by Boosting Solar Panel Power

The Economist recently highlighted a few promising developments in high-efficiency solar photovoltaic (PV) cells, specifically naming Oxford PV’s tandem cell technology, but the article neglected the punchline of what the impact would be (“Solar’s new power,” May 23, 2020). In fact, it could be quite significant. Some years ago, the cost of a solar plant was dominated by the cost of the panel, but now project costs are spread among a variety of categories. In the industry’s current stage, increasing the yearly power generation of a solar plant can be one of the most substantial ways to reduce cost since this affects the full stack of costs. To get the “$/MWh” to go down, boost the “MWh” in the denominator. Furthermore, there are several remaining major opportunities for boosting power generation for solar plants, including perhaps with Oxford PV’s technology.

What Is and Is Not Competitive about Concentrated Solar Power Technology

A nagging issue with solar power plants is that they generate power according to a schedule driven by irradiance, sun position, and characteristics of the power plant, but not according to the customer’s demand. Wouldn’t a great solar power plant product cater to a customer’s schedule? In many places, people use more power during the day than at night so daytime generation roughly meets demand well – at first. As more and more solar is added to a grid, the peak net demand shifts into the evening, and the value of the contributed solar power falls during the day. (Some nice analysis on this by Bollinger, Seel, and Robson at LBNL among others shows this.) The importance of responsiveness is increasing where there is copious solar on the grid.

Concentrated solar power (CSP) technology with integrated thermal energy storage promises to provide solar power that can more closely cater to customer demand. Coming in at ~1% of the total solar install base, CSP, well, lost the race to PV over the last decade. This is superficially explained by high cost. A quick look at why the cost is so high suggests that performance at a high level does not seem as much of an issue as practical matters. Continue reading “What Is and Is Not Competitive about Concentrated Solar Power Technology”

Performance Metrics and the Headache of Automotive Fuel Economy

“Look everybody, we gotta make this number go up! If we do that, we’ll win.” Maybe you can picture the meeting where a manager distills all of the analysis on how to improve the product down to a single performance metric. Everyone then goes back to work to do what he or she can about this special number. The metric could be a lot of things, such as product cost, cost of customer acquisition, or production rate. When done well, performance metrics can be useful because they reduce confusion and allow people to focus on one thing that, if improved, will make the bigger picture better. Continue reading “Performance Metrics and the Headache of Automotive Fuel Economy”

Patent Strategy for a Technology Startup: Part 2 of 2, Building a Portfolio Economically

In the last post, I highlighted some ways for gauging value of patents for a technology startup. In this post, the focus will be on thinking in terms of options to build a portfolio in an economic way. Continue reading “Patent Strategy for a Technology Startup: Part 2 of 2, Building a Portfolio Economically”

Patent Strategy for a Technology Startup: Part 1 of 2, Gauging Value

The world of patents sits at an intersection of law, business strategy, and technology. Whereas patent are legal documents and while the subject matter is technical, business strategy drives what should be pursued. In a technology startup, the patent portfolio is important, but the company is likely not blessed with experienced patent attorneys on staff. Someone has to work with outside counsel and figure it out. Continue reading “Patent Strategy for a Technology Startup: Part 1 of 2, Gauging Value”

Exploring High-Temperature Heat Pumps for Renewable Process Heat

The U.S. electric power industry has begun to make progress deploying renewable power to reduce its carbon footprint. A second bright area of decarbonization is that consumers of electric power, ranging from corporate goliaths like Google to single residences, have begun to contract for 100% renewable power. Companies can now go green by contract, if their energy use is electricity.

A harder nut to crack is how to provide process heat from zero-emission sources. Industrial plants, in many cases, use copious amounts of energy in the form of heat to drive processes. Just think of all the exhaust stacks at an oil refinery. Presume plant owners want to go green. How should they do it? Two factors make this problem more difficult than renewable electricity. First, the heavy hitters for renewable generation, i.e. hydropower, wind power, and solar PV power, do not make heat. Second, thermal energy is not transported cheaply.

This post takes a quick look at using a high-temperature heat pump to generate heat for an industrial process. The company would contract for renewable electric power and then use it to drive this heat pump. Continue reading “Exploring High-Temperature Heat Pumps for Renewable Process Heat”

Balancing Math and Story Time

Last week’s edition of The Economist published a story about how the U.S. Federal Reserve System writes the “Beige Book,” which is a short collection of anecdotes about the experiences of specific (but anonymous) people and businesses on things like wages, hiring, orders, etc. (“Storytime with the Fed: Low inflation means the Federal Reserve is changing whom it listens to” July 20, 2019) The Fed. compares these stories against their various analyses to form a better picture of what is going on in the economy. Apparently, the Beige Book really does affect their view points. The Economist’s article somewhat disdains their use of stories rather than just sticking with the numbers. After all, shouldn’t serious people follow the facts rather than getting emotional about heart-tugging stories? Continue reading “Balancing Math and Story Time”

Why haven’t we gotten green hydrogen for the Hydrogen Economy?

In his 2003 State of the Union speech, President Bush declared about hydrogen-fueled cars:

“With a new national commitment, our scientists and engineers will overcome obstacles to taking these cars from laboratory to showroom, so that the first car driven by a child born today could be powered by hydrogen, and pollution-free.”

Back in the early 2000s, the Hydrogen Economy had become all the rage in energy and environment discussions, and even the president caught the bug. The hydrogen car was going to be awesome because it was going to use a fuel cell that made emissions consisting of only water. While making a commercially-viable hydrogen fuel cell car a reality would be a major feat of engineering, government policy, and business, the real linchpin was where the hydrogen was going to come from. Getting it from natural gas would be a bummer because the whole point was that it should be a clean fuel! It needed to come from solar or wind power. Continue reading “Why haven’t we gotten green hydrogen for the Hydrogen Economy?”

Getting to a Fleet of Solar Cars

I told my brother-in-law that I had previously worked on car engines but now work at a solar company. He then said, “Oh really? Can you make a solar-powered rocket car? I want that.” (Sure, buddy…) Is he really in the market for the sustainable Batmobile? Like the majority of Americans, he buys used cars that burn gasoline. He’d be happy to use renewable fuel if it was cost-effective and available. If my brother-in-law is willing to compromise on the rocket engine, maybe we can still figure out how to do solar-powered cars. Continue reading “Getting to a Fleet of Solar Cars”