What would we do if cheap energy storage became a reality? We would put an end to carbon emissions from fossil fuel. The debate would be over. The missing pieces of the puzzle would be in hand.
This is something to contemplate. With recent changes in the cost of renewable energy, vital pieces needed for a dramatic conversion from fossil fuel to renewable energy allow enormous cuts in CO2 and toxic emissions. In order to leave behind fossil fuels for electricity, three conditions must be met:
1st, renewable energy must be abundant and cost-competitive
1.5 MW Battery demonstration at Maui windfarm. Credit: Energy Storage Association
We got this. Wind turbine costs and performance have improved so much that levelized power prices for new windfarms have reached a new low of 2.5 cents per kwh. This is comparable to the cost of running an existing gas or coal plant.
Solar has seen even sharper cost declines, turning what was a high cost niche technology into a widely-used competitive choice. The energy from new large-scale solar power projects is in the same price range (7-8 cents, unsubsidized) with energy from new coal and gas plants. Rooftop solar compares to retail prices, with huge numbers going solar now (over 500 per day average for 2014). By 2017, half the states will be able to have rooftop solar cheaper than local retail prices.
2nd, grid infrastructure and operations must be maintained and adapted for high levels of renewable energy
We are well on the way with this. Present-day experience in the U.S. demonstrates we are operating grids with wind providing over 25% of the electricity generated in the states of Iowa and South Dakota. In Texas and Colorado, wind has provided a record 40% and 60%, respectively, of electricity demand over an hour.
When any power supply is built, there needs to be wires built to send the energy to us customers. Transmission is still required when windfarms are built on farmland a long way from the city.
3rd, cheap and reliable energy storage must be able to fill in the power needs
This has two parts that are starting to appear. A combination of battery storage and imports of windpower from neighbors could keep the power supply working without fossil fuel when the sun sets and the wind moves with a weather front to supply the neighboring region. The biggest obstacle to making the transition off of fossil fuels is the slow pace of building the replacement infrastructure. If cheap and abundant storage can provide reliable support to the power grid, replacing coal and gas with renewables can be complete.
So what we need next is…
New storage technologies, batteries of various kinds, have to be cheap and reliable. The introduction of batteries with 10-year or 20-year lifetimes, with predictable performance, is a very new thing. The full suite of testing and standards, and building codes and fire safety certifications, is not yet available. For real scale, utilities and banks will need confidence from track records.
The DOE program that champions energy storage put forward a strategy for establishing the safety of energy storage systems across the portfolio of technologies and deployment types. Installations today are most certainly impeded by uncertainty over codes and standards. Unfortunate incidents of the past are too quickly recalled. As storage systems get larger, the science needed to understand the performance and thus the return on investment gets more complex.
The storage industry is going to grow with success by many, but will be set back by the failures of just a few. The electricity sector will need to be confident in the performance, the reliability, and the safety of new battery technology if society will be able to reap all the benefits that energy storage can offer.
And when we have all the pieces…
When we get all these pieces together, the combination of solar, wind and batteries will be able to replace all conventional power plants. Fossil fuels with CO2 and toxic emissions can cease to be part of the electric power supply. When we have these pieces, grid reliability can be met by non-polluting technologies.
The pace of wind and solar deployment will keep going without a breakthrough in storage. The grid will gradually change, as the economics and incremental technology improvements have their impacts. But a cheap and reliable supply of energy storage would change the whole story. The public should support policies and programs that ensure we get technology that is both cheap and reliable for our electric power needs.