#5 The Intermittency Myth

The intermittency of most renewable energy sources is something that is frequently trotted out as a reason we must continue to rely on fossil fuels for most of our energy needs. “The wind doesn’t always blow and the sun doesn’t always shine”.  But even with today’s technology, this argument is an obvious red herring from an industry that has gotten us into a very tight spot. There is no arguing that wind and solar power are not intermittent, but there are already technologies in place to deal with that, and many more coming quickly.

In fact, all of our current sources of electricity are intermittent. Nuclear power plants must shut down for refueling and maintenance, or be shut down entirely because of accident. Coal plants go off line because of supply problems or cleaning. Hydroelectric reservoirs are dependent on variable rainfall. But all these vagaries are dwarfed by the fact that the demand for electricity is incredibly variable! Just the normal variation in the population’s daily rhythms, not to mention a hot summer afternoon or a cold winter night, require that grid operators are constantly adjusting generation sources to give us our fabulously reliable energy fix.

Natural gas turbines have been a boon to the stability of our power grid for some time. They are small, can be distributed across the landscape and grid operators can turn them on and off quickly to meet fluctuating demand. Burning natural gas produces less carbon dioxide than other fossil fuels. These turbines will be necessary in the short run, but carbon free alternatives are readily available and we should begin to deploy them as quickly as possible.

PUMPED STORAGE— This method is not quick or easy, but it is a well proven technology already in use around the world. When there is a surplus, wind or solar energy can be used to pump water up to an elevated reservoir. When renewables are unavailable, the water is released to hydroelectric turbines to fill the gap. Pumped storage, most of it built in the 1970s, is currently used to store more energy than any other technology in the US.

WATER ELECTROLYSIS— This is an old and well proven technology. Surplus renewable electricity is used to break water into it’s constituent elements: oxygen and hydrogen. These can be stored, and later run through fuel cells to be converted back to electricity, or used for fuel in fuel cell powered vehicles, or simply burned in a gas turbine.

CO2 ELECTROLYSIS — This is a relatively new technology that will be the subject of intensive development. Excess renewable energy is used to remove CO2 from the atmosphere and turn it back into liquid fuel that can be used in multiple existing technologies.

THERMAL STORAGE — A simple and promising technology for decentralized domestic heating and cooling. When available, excess energy is used to heat or chill water which is held in an insulated tank. When renewables are not available, this water is used for heating or air conditioning.

ELECTRO-CHEMICAL STORAGE — Batteries. There have been tremendous advances in this technology, but it is currently a small player in the electricity market. However, it will become a huge storage source as the world converts to electric vehicles. With hundreds of millions of electric vehicles spending up to 90% of their time plugged in to a reversible charging station, they can form giant grid scale batteries. Tiny withdrawals from each vehicle can be used to stabilize the grid, to be replaced as soon as renewable sources come back on line.

There are other electric storage technologies on the near horizon, but I think you get the point — there is no reason not to make a huge push to install renewable sources!

THINGS YOU CAN DO:

* When folks tell you that we can’t switch quickly to sustainable power, push back! Tell them that the sun provides vastly more energy than we need every day, and that we already have the technology to harvest it. 

* Learn about how the public utilities in your state are regulated and about the political contributions they make. These vary  greatly by state.  You may be shocked!

* Those that say we cannot quickly convert to sustainable energy are the ones that stand to make money from the status quo — electric monopolies, fossil fuel extractors, and the politician that they have bought. They are seeking to build additional fossil fuel generation before its absurdity becomes obvious. Write to your representatives in government and the utility commissioner of your state.

To learn more about how the electric grid will work with renewables, check out:  Yale Environment 360
To learn how some utilities use dark money to lock in fossil fuel generation see:   Audubon News

Thanks for reading,

Doug Hylan Brooklin, Maine

“We are the first generation to feel the sting of climate change, and we are the last generation that can do something about it.” – Jay Inslee