by Judith Curry
Looking ahead towards new energy technologies, plus my own saga and rationale for transitioning my personal power generation and consumption.
Happy New Year everyone! The theme I decided for my post to ring in the New Year is one of optimism re new technologies.
The basis for this post is an article by Eli Dourado that I spotted on twitter: Notes on technology for the 2020’s. Will the new decade be the roaring 20’s or the boring 20’s?
Topics covered by Dourado include:
- Biotech and health
- Energy
- Transportation
- Space
- Information technology
All are interesting and worth reading, here I focus on Energy.
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Energy
The 2010s were the wind and solar decade. We observed stunning declines in the cost of both, although total deployment of wind and solar remains small—in 2019, wind and solar represented less than 9 percent of utility-scale electricity generation in the US. In the 2020s, cost declines will likely stall—wind and solar are already pretty cheap, so the declines of the past decade are not reproducible. Deployment, on the other hand, will accelerate.
Mass deployment of wind and solar will bring challenges. These sources are highly intermittent. When the wind suddenly stops blowing—which happens—we need a way to quickly make up the deficit. Each of the three electricity grids in the continental US—east, west, and Texas—has to remain in supply-demand balance every second of every day. We can use grid storage to smooth out some of the bumps, but storage remains expensive. To reach a grid powered entirely by today’s renewables, we would need storage at a price of $20 per kWh (with caveats).
That storage doesn’t all have to come from batteries, but let’s talk about batteries for a bit. Using Tesla’s grid-scale Powerpack as data, a 232 kWh battery today costs $125,793. That is a price of over $542/kWh. Through innovation, that pricetag will come down over the course of this decade, but improvements on the supply side could easily get swamped by increases in demand. After all, this decade will also include a huge shift toward electric vehicles, which I will discuss below. When demand outpaces supply, prices tend to stay high, even when there is impressive innovation.
With increased deployment of intermittent power generation, increased total demand for electricity due to electric vehicles, a high cost of grid storage, inadequate electricity transmission (have I mentioned that we often neglect to build in this country?), and strong political support for decommissioning fossil fuel plants, the 2020s may be a time of electric grid instability. This could be tempered to some extent by using car batteries as grid resources and through (politically unpopular) variable electricity prices.
JC note: this article is much more bullish on solar and particularly wind than I am. The article neglects the challenges of scaling up in terms of land use, resource availability, and seems to accept some level of grid instability.
Ultimately, we need scalable zero-carbon baseload energy, which means nuclear or geothermal. The problem with nuclear is the high cost. If you look at NuScale’s small modular reactor technology, they are targeting 6.5¢/kWh. That is baseload power, so not directly comparable to wind and solar’s intermittent generation costs, but even so, it isn’t the most competitive in today’s market. Furthermore, NuScale’s flagship project was just delayed three years and is now not scheduled to come online until 2030.
JC note: Dourado is less optimistic about nuclear costs than others.
What is more plausible this decade is enhanced and advanced geothermal systems. The legacy geothermal industry is sleepy, tapping energy at traditional volcanic hydrothermal hotspots—forget about it. The next generation of the industry, however, is a bunch of scrappy startups manned by folks leaving the oil and gas industry. The startups I have spoken to think with today’s technology they can crack 3.5¢/kWh without being confined to volcanic regions. With relatively minor advancements in drilling technology compared to what we’ve seen over the last decade, advanced geothermal could reach 2¢/kWh and become scale to become viable just about anywhere on the planet. Collectively, the startups are talking about figures like hundreds of gigawatts of generation by 2030. I’m watching this space closely; the Heat Beat blog is a great way to stay in the loop. As I wrote last month, permitting reform will be important.
JC note: geothermal is the hottest energy technology that is feasible and cheap that I don’t know enough about. The linked article by Dave Roberts (first line in preceding paragraph) is very good.
Fusion continues to make technical progress. I expect we will get a demonstration of energy-positive fusion in this decade from one of several fusion startups or perhaps Lockheed Martin’s compact fusion reactor. But again: a demonstration is far from a change that transforms society. It will take further decades to deploy reactors onto the grid. By the time fusion gets there, the energy market will be quite different from when we started working on fusion reactors in the 1940s. Wind, solar, and hopefully geothermal will make electricity pretty cheap, and fusion will struggle to compete.
JC note: I don’t see a long term future for wind energy if there are other economical, clean options available. If fusion energy was available, I imagine that it would be a very attractive option. See also this article on fusion energy.
Consider: around half the cost of an advanced geothermal plant is drilling, and half is conversion equipment. Suppose the plant is amortized over 30 years (although many geothermal plants last longer), and after that period the conversion equipment needs to be replaced. But the hole in the ground does not need to be replaced! That means for the next 30 years, electricity can be generated at half the initial cost. Geothermal wells we dig this decade could be producing at less than 1¢/kWh by the 2050s. That is a tough market for fusion to break into. But fusion will still be a great source of power in applications where other sources aren’t available, such as in space.
The 2020s will be a big decade for sustainable alternative fuels (SAF). Commercial aviation can’t electrify—batteries will never match fossil fuels’ energy density. Given political realities, aviation has no choice to decarbonize, which means either hydrogen fuel or SAF. Hydrogen fuel is much better than batteries, but still not as energy dense as fossil fuels or SAF, and so my money is on SAF, and particularly on fuel made from CO₂ pulled from the atmosphere. It is easy to convert atmospheric CO₂ to ethanol in solution; and it is easy to upgrade ethanol into other fuels. But it is hard to separate ethanol from water without using a lot of energy—unless you have an advanced membrane as Prometheus Fuels does. I have written about Prometheus before and continue to follow them closely. Their technology could decarbonize aviation very suddenly.
JC note: SAF and Prometheus Fuels are new to me. Thoughts?
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JC’s energy transition
A few notes on my personal transition to cleaner energy. About 6 years ago, we needed to purchase some new appliances: hot water heaters, stove top, clothes dryer. At the time we opted for natural gas appliances – they were more energy efficient and operated more towards our preferences (not a fan of electric stove top or electric clothes dryer). I now realize that natural gas stove tops are not good for indoor air quality; had we realized that at the time, this might have swayed our decision. We also bought a new car about 5 years ago – internal combustion; we really need 4 wheel drive where we live and at the time there weren’t good hybrid or electric options.
About 2 years ago, we decided to make the plunge for rooftop solar for our home, this was eventually installed about a year ago (5 years ago, we wouldn’t have seriously considered solar, owing to cost and available technologies). We also purchased two Tesla Powerwalls, which allows us to generate power for our household if the grid electricity is down and also at night. As a second backup, we opted to keep the natural gas Generac (no simple task to integrate this with the Powerwalls). After tax breaks and rebates, all this cost us about $40K. Based on our current electricity use, we will break even in about 15 years.
Caption: 48 solar panels on south facing garage roof. Tesla Powerwalls (two white vertical rectangles) and Generac (white box on the ground)
The primary motivation for us to go solar was energy security (we already had a natural gas Generac backup system); we would not have gone solar without the Tesla Power Walls. The Generac was kept to provide power in the event of wildfires drastically reducing the incoming solar radiation (a situation which is not unusual in the Sierra Nevadas). Our local power generation in Nevada is already pretty clean, with abundant renewables including geothermal; local air pollution is low and mostly generated by automobiles. $40K would have been a lot to pay for ‘virtue signalling’ for clean energy, when our local power sources are already pretty clean.
The next point I want to make is how the infrastructure of solar power changes your outlook on future purchases of appliances, cars, heating and air conditioning. Re air conditioning, while we have air conditioning in the house, we use a swamp cooler (powered by electricity) which our climate allows and which we vastly prefer owing to to the ventilation. Not clear that electric vehicles are the right decision at this point (our existing cars are running fine). We will probably replace the natural gas hot water heaters in the relatively near term, provided that our existing ones can be somehow/somewhere be re-used.
Our house was built in the 1980’s, with a fairly ingenious passive solar design that allows mid winter sun to pour into the house, both directly into living spaces
and also into higher levels, where it warms up stone walls, also with ceiling fans to bring the heat downwards.
In summer, when the sun is angled higher, little sunlight enters into the house. So our wintertime heating bill is relatively low. But over the next 5 years we will probably replace our 3 gas furnaces, will look seriously into heat pumps and alternatives to natural gas furnaces.
JC reflections
There are two broad issues here, extending from my personal anecdotes.
Energy infrastructure matters – once infrastructure is in place (home solar, charging stations for electric vehicles, whatever), decisions to move towards cleaner and more efficient use of energy become much simpler.
Second, your ‘best’ decisions made now may become suboptimal in ~5 years time, but you are locked in by the infrastructure (appliances, power plant, whatever). Bottom line is that ‘urgency’ to improve in a ‘green’ direction can backfire; wait until the appliance, power plant whatever comes to the end of its useful life and there will be better options.