A clean energy future will require innovation and creativity, including an increase in investment in high-efficiency energy solutions. But once we eliminate the kinks — and the misconceptions — it is a bright future.
As we increase the percentage of electricity generated from renewables, one of the concerns is intermittency and the need to meet peak demand that can — and often does — occur at the same time renewables are not generating (or not generating as much). In fact, this fear is the basis for half-baked claims (including from people in prominent positions) fueling the fear that there will not be power when it is needed.
One of the things I remember being amazed by when I lived in Germany as a teenager was the funicular railways — all that was needed was a water supply and a slope. Passenger cars are joined by a steel cable that runs over pulleys at either end and underneath the cars. The cars travel up and down on a single track, which separates where they pass each other in the middle. The cars are loaded and then water from a nearby source is added to a ballast tank on the upper car until it weighs enough to have the force of gravity pull the lower car upwards. When the cars reach their destinations, the lower one can be drained and the upper one filled. Some pump the water up, but the real genius is using only the water, diverted from a nearby stream or river to power the system.
What does this have to do with renewables?
We can move the discussion about renewably generated electricity (and concerns about the intermittent nature of some of those sources) to one beyond batteries and the need for the component metals and ‘end of life’ questions, and start talking about energy storage. The fact is that if we start thinking of energy in all its forms — both potential and kinetic — there are other ways that we can harness one to help provide the other.
This helps advance the growth of renewables because when wind and solar (or, in fact, any sources) are producing more power than is needed, it can be saved for those times when demand outstrips supply.
One of the issues is the ability to come online quickly, when generation dips or when demand soars. That’s one of the advantages of natural-gas fired power plants — they ramp up quickly to meet capacity demand. Natural gas has long played this "peaker" role in US power generation and will continue to do so. This can happen as hybrid solutions at the individual power plant level, it can happen on the demand side of the grid, or we can continue the current trend of adding traditional natural gas generation to the grid.
Similar to my train example, pumped storage plants harness the power of water, by using two reservoirs at different altitudes. When electricity is being generated, some is used to pump water from the lower to the upper storage area. When power is needed, the water is released; through turbines, generating power as any other hydroelectric plant. This is not a new or radical concept; in fact, Duke Energy’s Jocassee Hydroelection Station came online in 1975. The Blenheim-Gilboa Pumped Storage Power Project, about 60 miles from Albany, uses hydroelectric technology and two large reservoirs at different altitudes to generate up to 1.16M kilowatts of electricity. A similar concept is using compressed air, which requires a large cavern or storage space.
Another promising technology, Vandium Flow batteries, last for more than 20 years, discharge 100 percent of the stored energy and can be used seemingly over an unlimited number of cycles. They require Vandium, which can exist as several ions of different charges in solution. V-flow batteries use the multiple valence states of vanadium to store and release charges.
In short, the clean energy future is one that will require innovation and creativity, including an increase in investment in high-efficiency energy solutions. But make no mistake, once we eliminate the kinks — and the misconceptions — it is a bright future.