Photovoltaic & Storage for Fall 2021, Part 3, States, Megafactory

"Utilities building solar and wind farms are increasingly pairing these with large batteries to store excess energy to discharge to the grid later."

John, that many developers are building battery storage in proximity to solar or wind farms does not mean they share an electrical connection, or that exclusively clean energy will be stored.

To my knowledge none are configured that way, and there would be no financial reason to do so. They're storing electricity from a grid mix, and increasing its emissions by anywhere from 104 - 407 kg/MWh in the process.

They are effectively arbitraging energy - buying it whenever it's cheapest, and selling it when it's most expensive. It may result in a reduction in emissions sometimes, but it will always waste energy, and could very well result in a net increase in emissions.

"Pairing" wind and solar farms with storage is a non-solution, a visual artifice designed to capitalize on the naïveté of renewables advocates - fruit that's always ripe for the picking.

Good stuff John.

I mostly track the Western States... Right now, I see signed contracts for about 10,000 MW/35,000 MWh of storage out West over next few years.  I'm guessing that number will increase to at least 50,000 MWh by end of 2025.

Eventually, most of the existing solar plants will have battery storage added on site. Standard size will be same as max interconnection at the location and for now duration standard is 4 hours.  So, for existing 100 MW solar plant - a 100 MW/400 MWh battery will be added.

Here is a recent example of proposed battery project being added to existing 250 MW solar installation - Silver State South - in Nevada. 

Note: there is about 20,000 MW of Utility scale solar capacity in Western states currently.

Tough to get accurate information on the impact on energy costs for these installations. Not too surprised, as the that is not much of a consideration for democratic politicians.

Is relatively easy to figure out, as basic parameters are net installed cost ($kW) and capacity factor of battery/solar energy facility. That net energy cost is clearly higher than a solar facility by itself. A simple cycle gas turbine with battery facility very likely has a much lower energy cost. Combined-cycle and battery, probably lower, but that depends on the capacity factor for the combined-cycle unit.

I think Bob is right, however. Basically a means for investors to rake in cash with basically zero risk because the government subsidizes the scheme.