Are There Batteries In the Grid's Future?

 

Texas has the largest installed capacity of wind generation of any U. S. state as of 2019.  But all those windmills did no good a year ago when historically low temperatures knocked out natural-gas production and generators, leading to the Big Freeze and the deaths of over 200 people.  The reason?  There was almost no wind associated with the cold snap, and no wind means no wind generation. 

 

In the debate about the Texas power grid that followed, some charged that our increasing reliance on wind power (and to a lesser extent, solar power) was destabilizing the grid.  Up to now, at least, power has to be generated on demand, so electric-utility operators have come up with a combination of base-load and peak-load generators to deal with the fluctuations in demand, which can go very low at 2 A. M. on a mild spring day, but soar to many times the minimum on a blazing August afternoon.

 

Base-load generators are most efficient when they run all the time.  Nuclear power is in this category, as are fossil-fuel plants that use steam turbines and large boilers fired by natural gas (or, decreasingly, coal).  These types of plants are used for base loads because starting and stopping them is a big deal and can take hours or even days. 

 

Peak-load plants, on the other hand, are designed to come on line in just minutes.  One example is the gas-turbine plant, basically a bunch of jet engines hooked to generators.  Peak-load plants are typically less efficient than base-load plants, but they can be started up quickly to meet soaring demand in emergencies. 

 

Solar and wind don't fit either of these categories, as they depend on whether the sun's out or the wind's blowing, respectively.  Fitting the fairly unpredictable output of these renewable types of energy into an existing grid can be challenging, because it adds fluctuations that weren't there before.  If the wind's blowing hard and Texas is getting up to 10% or more of its total electricity demand met by wind energy, and all of a sudden the wind stops, you have to be ready to jump in with peak-load plants and supply what's missing, and that isn't always easy.  So as more fluctuating renewables are added, the problem of managing the grid to meet fluctuating demand gets even harder.

 

Although experts determined that this issue was not a primary cause of the February 2021 Texas blackout, it's an ongoing concern, and one way of dealing with it is a very old one:  batteries.

 

Using batteries as electric-utility energy storage is not a new idea.  I have a 1910-era book on my shelves that describes how electric-streetcar power plants were supplemented by banks of lead-acid batteries attached across the lines at strategic places along the streetcar routes.  In periods of light demand with low traffic, the batteries were charged by the central power plant.  And during rush hour when there were more trolleys on the line than usual, the batteries would discharge into the overhead wires and supplement the base-load power generated at the central plant.

 

The problem with lead-acid batteries is that it takes a huge number of them to store enough energy to make a difference with a large-scale power grid.  Depending on the technology, a lithium battery of the same volume as a lead-acid battery can store up to ten times the energy, and the weight advantages are even better.  That's why electric cars had to wait until lithium batteries were fairly practical to compete with internal-combustion cars. 

 

In December of 2020, Vistra Energy connected what was then the largest battery-storage energy facility in the world to the California grid at Moss Landing in Monterey County.  The system can provide up to 300 MW of power and can store 1.2 gigawatt-hours, implying that it could provide its peak energy output for three or four hours before pooping out.  But that is plenty of time to tide a grid over an emergency until other more conventional sources can be put online.

 

Actually, because batteries can start supplying massive amounts of power in less than one cycle of the 60-Hz power frequency, they are very useful for damping out short-term instabilities in power grids that can otherwise trip relays and cause blackouts.  This type of operation can't be done with mechanical generation systems.  So a battery storage facility like this is one more tool in the power-dispatcher's toolbox to use in meeting fluctuating demand.

 

The Moss Landing facility was in the news recently because of a fire that destroyed ten of the nearly 100,000 battery packs at the facility, the second such fire in five months.  The first fire was caused by leaking water from cooling pipes, and so the second one may be due to similar causes.  The fire was contained and out before the fire department had a chance to do anything. 

 

The nice thing about battery systems is that failures can be isolated fairly easily, as the Moss Landing mishaps show.  Although the plant was shut down during the fire for safety reasons, repairs are fairly straightforward and the system was back online in short order.  This feature of gradual degradation is a big asset in the utility business, where shutdowns can cause big headaches.

 

It remains to be seen how significant a role battery storage will play in the future of the so-called smart grid.  Electric-car makers such as Tesla have dreams of distributed battery storage, in which thousands or millions of electric cars plugged in overnight could serve as a virtual storage facility controlled by the electric utility they're plugged into.  That would require massive changes in both hardware and regulatory structures that I'm not sure we're ready for.  But it's a nice dual-use idea that might evolve into a much more reliable, robust, and efficient grid than the fairly brittle things we have now. 

 

When I worked at an electronics repair shop one summer in college, I'd be amused when a customer would say, "This radio isn't electric, it runs on batteries."  In the future we may all be running on batteries more than we realize, and the grid will be more stable as a result.

 

Sources:  The website www.vice.com carried a story about the Moss Landing fires at https://www.vice.com/en/article/dypw5x/largest-lithium-ion-battery-in-the-world-meltdown-moss-landing.  I also referred to the Wikipedia articles on "Wind generation in the United States" and "Battery storage power station."

 

Residential Solar Energy: Power to How Many People?

A friend of mine recently installed an array of solar panels (photovoltaic generation) on his roof.  It's part of an Austin Energy plan that makes it straightforward for well-heeled consumers to get a turnkey installation done.  After a stretch of sunny days he'll meet me for lunch and tell me how much power he sold to the utility that week. 

I was reminded of this when I read a recent article by environmental writer Bill McKibben in The New Yorker.  Entitled "Power to the People," McKibben describes how residential solar-power installations such as the one at my friend's house are getting cheap enough so that ordinary blue-collar workers and other middle-class types can afford them, at least when their electric utility cooperates in various ways.  McKibben starts his piece with the story of a couple in Vermont who had their house made over for energy conservation and production:  better insulation, a heat-pump heating unit, all-LED lighting, and a solar panel on their garage.  After the installations, their electricity usage for a heating season (October to January) went down by 16%, and they were able to get by without starting up their old oil-burning furnace at all. 

McKibben is supporting the presidential run of Bernie Sanders, the far-left independent senator from Vermont.  But to read his New Yorker piece, you might not guess it—he sounds more like a free-market libertarian.  His main point is that it's starting to make not only environmental and political sense (depending on your view of the environment and politics) but economic sense for more people to go solar and invest in energy-saving technology, simply because it's getting cheaper to do so.  And so McKibben is looking to the free market to do what his years of playing a prophetic Cassandra in the wilderness of environmentalism haven't done so far:  to foster a major move away from fossil fuels and toward renewable energy for electric power.

 While I welcome Mr. McKibben's newfound friendliness toward the market economy, one can question how realistic his optimism is.  As he points out in the article, one of the main obstacles in the way of further adoption of solar power in private housing is the electric utilities themselves.  While some, notably in California and Vermont, have been in the forefront of renewable-energy initiatives, others feel threatened by the idea of home-grown electricity.  And the reason is money. 

Nearly all electric utilities are regulated to some degree by state utility commissions, which allow them to set rates that guarantee a certain profit in exchange for highly reliable delivery of power.  This sort of environment fosters conservative behavior and a set of rules that favors the status quo.  For example, if people start making their own power, who pays for the expensive and maintenance-intensive electric grid, especially if more and more fossil-fuel-burning power plants that feed it are shut down?  The economic incentives built into the system were not designed for power to go backwards, and it's not clear how the organizations that operate distribution networks are going to get paid for what they do in a highly distributed power-generation situation such as the use of extensive solar power would create.

Here in Texas, things are a little less regulated than in other places.  It's not quite true here, as McKibben states in his article, that "utilities are granted exclusive rights to a territory."  That's true for electric distribution companies, but not for electric generation in Texas, where most electric-utility customers can choose from a variety of generation sources, including renewables such as wind power.  And partly due to a recently phased-out subsidy, Texas leads the nation in terms of wind-powered electric generation.  So in a way, there's evidence even in fossil-fuel-friendly Texas that what McKibben hopes will happen is already happening.

But a totally free market for electric power is almost inconceivable, and so we have to look soberly at what it would take for renewables (solar being the newest contender) to make a significant dent in the use of fossil fuels for electric power in the U. S.  According to the U. S. Energy Information Administration, about two-thirds of all electric power in the U. S. is produced by burning coal, oil, or natural gas.  Say we wanted to reduce that fossil-fuel usage by a third, out of concern for climate change and so on.  Anything smaller would be a drop in the bucket  (and we're not even getting into the question of what other countries are doing and whether this U. S. contribution would make a difference globally).  That's about a trillion kilowatt-hours per year (10¹⁵ watt-hours, for you exponential-notation fans).

Now, suppose everybody—not just upper-class environmentalists, but everybody in every kind of rental and owner-occupied housing in the U. S.—installed solar panels with an average generating capacity of 5 kW, which is the typical size for residential installations.  That is an upper limit, by the way—clouds, nighttime, and other issues mean that you don't get 5 kW twenty-four hours a day.  Even if everybody had solar panels, we would still need the utility network for emergencies, to ship surplus power to places where it was needed, and so on.  The question is, would we be able to make a dent in that trillion kilowatt-hours?

My very sketchy back-of-the-envelope calculations say yes, sort of.  You would still need peak-capacity generators hooked to the grid to deal with hot days and so on.  But yes, you could afford to shutter a lot of old coal-burning power plants if everybody installed solar panels.

And while we're dreaming, how would we pay for all those solar panels?  A typical residential solar installation today is still expensive—$18,000 might be a typical actual cost, not including subsidies, tax breaks, and so on.  While this figure is going to decline in the future, it can't follow the path of Moore's Law and get down to practically zero, because there's a certain amount of labor involved, and even if we could make solar panels for free they don't climb up on the roof by themselves.  Multiply $18,000 by over a hundred million U. S. housing units, and you get $1.8 trillion.  The U. S. federal budget for 2015 is $3.8 trillion.  As you can see, this solar-installation idea is not a trivial deal.  Even if it were spread out over a decade, you'd be spending each year as much on solar panels in the U. S. as one optimistic solar-industry estimate says annual global sales will be by 2021.

Yes, it could be done.  But I think it's clear that unless there is a huge degree of government intervention in the forms of subsidies, incentives, or other external market manipulation, the free market isn't going to put solar panels on everybody's roof any time soon.  Maybe President Bernie Sanders could do it, but offhand I can't think of any other way.

Sources:  Bill McKibben's article "Power to the People" appears in the June 29, 2015 edition of The New Yorker, pp. 30-35.  I used statistics on the fraction of electric energy produced with fossil fuels from the website http://www.eia.gov/tools/faqs/faq.cfm?id=427&t=3.  The Solar Energy Industries Association website www.seia.org has plentiful data on historical and current trends in solar-energy installations.  The 180-billion-sales-by-2021 figure is from http://www.solarmaxtech.com/global-solar-market-could-exceed-180-billion-dollars-by-2021/. 

Global Warming, Solar Energy, and $300,000 Tortoises: The Morality of Energy Production

On Tuesday, June 25, in a speech before enthusiastic students at Georgetown University, President Obama delivered a message outlining his vision for what the United States ought to do, and what he personally is going to do, about the moral issue of energy production.  Now at first glance, you would think that energy production is a technical issue that should be left to engineers and economists.  But it was clear from the President’s speech that he thinks it is also a moral issue, as moral as which side you should fight on in a war.  His speech, in fact, was peppered with militant terminology.  He spoke of having the “courage to act,” he talked of the “fight against climate change,”  and expressed his desire for America to “win the race for clean energy.”  Toward the end, he called for citizens “who will stand up, and speak up, and compel us to do what this moment demands.”  To that end, he announced that he was going to ask the Environmental Protection Agency (EPA) to issue regulations that, according to Obama critic Charles Krauthammer, will “make it impossible to open any new coal plant and will systematically shut down existing plants.”

If the construction of new coal-fired power plants is going to come to an end, maybe we can start building more Ivanpahs instead.  Ivanpah is a Piute term meaning “good water,” and is the name of a giant solar-energy project not too far from where Interstate 15 crosses the California-Nevada line on its way to Las Vegas.  Built by a consortium of construction and solar-energy firms, plus money from Google investors, Ivanpah consists of three circular arrays of tracking mirrors that direct sunlight onto four-hundred-foot tall “power towers.”  Atop each power tower is a cubical black boiler to make steam that turns turbines that drive generators to make electricity.  This is the kind of thing that President Obama sees as the future of energy production:  it is solar-based, it adds nothing in operation to the nation’s carbon footprint, and it is even respectful of the rights of the 150 or so desert tortoises on the construction site who were carefully inventoried and transported to an equally suitable habitat at a cost of about $50 million—or roughly $300,000 per tortoise. 

The engineer in me applauds the Ivanpah project.  It is an elegant yet simple solution to several of the problems that plague direct photoelectric energy production using solar cells, one of which is the fact that all days are not equally sunny.  When clouds show up, energy production from solar cells drops instantly, and this is not the sort of behavior that power grids like. 

The Ivanpah plant mitigates the cloud problem in a couple of ways.  First of all, unless there’s a solid cloud cover (not too common in the desert), smaller cloud shadows won’t put the five square miles of mirrors out of commission all at once.  And even if insolation, as it’s called, varies over a time period of minutes or even hours, the thermal inertia of the large power-tower boilers means that the plant will still be producing energy even when it is temporarily in the shade due to clouds.  So without any extra effort, the Ivanpah project has sidestepped one of the significant technical obstacles faced by solar-cell arrays.

Still, Ivanpah is expensive.  According to Wikipedia, the whole project, now nearing completion, will cost about $2 billion when finished.  This is roughly four times what a new coal-fired plant of equivalent peak output would cost.  And the coal plant will run any time you want it to.  True, you have to buy coal over the life of the plant, but this can be factored into the cost, and the economics of that calculation tells you why so much of our electric energy is still supplied by coal.

If we stopped building new fossil-fuel power plants tomorrow and allowed only nuclear, solar, and other renewable forms of new plant construction henceforth, several things would happen.  Electricity would become gradually more expensive and possibly less reliable than it would be otherwise.  And America’s contribution to the world’s output of carbon in the atmosphere, which has already fallen to 1992 levels, would fall faster and be overwhelmed by the soaring use of coal and other fossil fuels by China, India, and the rest of the world.  The overall objective effect on global warming would be minimal.

Everyone has a moral compass that helps prioritize ethical decisions.  For most people, murder is a more significant moral issue than jaywalking.  President Obama views the threat of global warming as a moral equivalent of war, to judge by his Georgetown speech.  He clearly wishes to unite the country around a common set of sacrifices that will allow us to hold our heads up before our grandchildren, whose world we should literally save from destruction by the evil forces of climate change.

I will merely point out, as Krauthammer has, that climate change comes in dead last in a poll of 21 matters of concern to Americans.  Jobs and the economy are things that the average U. S. citizen is far more concerned about, but the President’s moral compass seems to be insensitive to such concerns.  Or perhaps, as a practical politician, he realizes that in his lame-duck term he should spend his limited time on matters where he can act unilaterally, as with his instructions to the EPA, and not waste his energy on proposals he will not be able to get through Congress.  Leadership is a mysterious thing, and some leaders who have received the laurels of historical honor were excoriated and criticized at the time.  The President obviously feels he is in this category, and often refers to his unpopular proposals as being on the “right side of history.” 

But there sometimes is not much difference between being ahead of the pack and simply being out in left field.  If there was a truly united sense among Americans that the nation was under an existential threat and climate change was the culprit, President Obama’s rhetoric would fit the national mood and history might go his way.  But I fear what we are witnessing is instead the desperate actions of a leader who wants to force his vision of the future on a public that is unwilling to pay the high price for a dubious honor that may not come for generations, if ever.   

Sources:  I learned about Ivanpah from the print edition of the June 24, 2013 issue of Time Magazine.  I used information from the project website http://ivanpahsolar.com, President Obama’s speech of June 25 as transcribed by the Wall Street Journal at http://blogs.wsj.com/washwire/2013/06/25/full-transcript-of-obamas-remarks-on-climate-change/, Charles Krauthammer’s column for July 6, 2013 as presented in the Pittsburgh Post-Gazette at http://www.post-gazette.com/stories/opinion/perspectives/charles-krauthammer-obama-will-risk-the-economy-for-no-impact-on-climate-change-694450/, and the Wikipedia articles on “Ivanpah Solar Power Facility” and “Fossil fuel power station.”