More than 8 years ago, researchers from the University of Delaware (UD) and Delaware Technical College (DTCC) put forward a rather “radical” idea — to deal with wind and solar power’s intermittency while also acknowledging wind and solar power’s falling costs, why not just overbuild wind and solar power plants in the future?
Before I get to the study results, here’s the basic idea in more detail:
- A certain amount of wind and solar power plant capacity on a utility grid will meet 100% of electricity demand one day out of the year.
- A larger amount of wind and solar power plant capacity on a utility grid will meet 100% of electricity demand 10 days out of the year.
- An even larger amount of wind and solar power plant capacity on a utility grid will meet 100% of electricity demand 100 days out of the year.
- Each time you increase wind and solar power plant capacity to meet 100% of demand on more days, that means electricity supply from those power plants is exceeding 100% of demand on days with more sun and wind relative to demand.
- Naturally, it costs more money to build more wind and solar power plants, so it’s not intuitive to plan to build more solar and wind capacity than is needed for, let’s say, 300 days out of the year.
- But, if building more solar and wind capacity than is needed for 300 days out of the year in order to satisfy electricity demand the remaining 65 days of the year is cheaper than building other sources of power to fill in the gaps between solar and wind, then it just makes sense to “overbuild” solar and wind power plants for those 300 days a year.
As noted at the top, researchers from the University of Delaware (UD) and Delaware Technical College (DTCC) decided to examine this matter for a large chunk of the United States to see what would be the most economical solution in net by 2030. Their conclusion in 2012 was: yes, just overbuild wind and solar, with some energy storage and fuel cells mixed in.
“Researchers used a model with 28 billion combinations of storage schemes, and renewable energy sources. Each combination was tested over historical hourly weather data and electricity use over a four-year span. Analysts used data for the model from PJM Interconnection, representing one-fifth of the US electricity grid, which spans 13 states, ranging from the Midwest (Illinois) to the East Coast (New Jersey). …
“Meanwhile, the report found that, creating more electricity than required during regular hours to meet high energy use (but during low wind hours) would have lower costs compared to storing the excess energy for higher consumption later (of course, this is based on the assumption we won’t see any storage breakthroughs in that time).”
Much has changed since 2012. The biggest thing that changed in this industry is that solar power costs came down much quicker than expected. Battery costs have also come down faster than most analysts expected. The result with regards to this study is clear: it makes even more sense to simply overbuild cheap wind and solar power plants than to try to fill in the gaps between supply and demand using fossil fuel power plants. Even leaving environmental matters out of it, it’s simply cheaper to overbuild low-cost solar and wind power plants.
What seemed like a radical idea back in 2012 is gaining increasing support today. More and more people see that, indeed, solar power, wind power, and batteries have become cheap enough that you don’t need “baseload power” or other filler power plants in many places.
Naturally, the precise splits in energy sources and how much they are overbuilt is something best explored for individual regions or utility districts. In some places, it may make most sense to have 40% solar power, 50% wind power, 10% something else. In another place it may make most sense to have 70% solar power, 25% wind power, 5% something else. The good news is, on that topic, Mark Z. Jacobson of Stanford has actually done the work. See the first four related stories below for more on that
- 100% WWS Part 1: Jacobson’s New Study Displaces 99.7% Fossil Energy With Massive Savings
- 100% Wind, Water, & Solar Energy Can & Should Be The Goal, Costs Less
- Transitioning the World to 100% Renewable Energy
- Transitioning the World to 100% Renewable Energy — Part 2
- Solar Costs & Wind Costs So Low They’re Cheaper Than *Existing* Coal & Nuclear — Lazard LCOE Report
- 100% Renewable Energy, Tesla in the Early Days — #CleantechTalk with Mark Z. Jacobson
- City of Houston Surprises: 100% Renewable Electricity — $65 Million in Savings in 7 Years