A Tesla Investor Day Wish: Vehicle to Grid Support
A no brainer for more grid-accessible energy storage
Elon is saying tomorrow’s Tesla Investor Day will include the path to a fully sustainable energy future for Earth. Much cheaper vehicles would be awesome. So would a smaller-scale home battery. But I hope Investor Day includes Tesla formalizing Vehicle to Grid support.
The sun isn’t always shining and the wind isn’t always blowing. The transition to renewable energy needs effective energy storage and responsive energy sources. Vehicle to Grid helps deliver that by enabling power stored in EV batteries to flow back to homes and the grid.
Tesla’s fixed energy storage business is booming with Powerwalls and MegaPacks. In 2022, their installations were up 64% YoY to 6.5 Gigawatt Hours (GwH) of new installations. That amount is roughly what it takes to store 5 china-scale coal power plants of energy for an hour.
However, there was much more energy storage collectively shipped in Tesla’s car batteries than in Powerwalls and Megapacks. Using standard Model 3 battery info, Tesla shipped 80.6 GwH of energy storage in its cars last year. To be fair, that’s not an apples to apples comparison. The vehicles won’t always being plugged in, they are supposed to be out driving after all! Still, that’s 12x more energy storage than in Powerwalls and MegaPacks.
Vehicle to Grid support would be great for two reasons:
1) It enables the grid to tap into this huge, existing energy storage resource. OhmConnect has shown that scheduled demand response can be effective.
2) It can make the renewable transition cheaper by reducing the amount of new energy storage that needs to be built, and possibly making EVs cheaper with a demand response billing plan. I could imagine a new vehicle lease plan where you get $50 off your monthly payment as long as you keep your car connected, with energy, for 10+ hours during peak demand windows.
Tesla has already winked at this being a possibility soon. The technical spec of Tesla’s charging standard (NAC) published last year showed it could support Vehicle to Grid. Elon talked about Vehicle to Grid at Battery Day in 2020. And Tesla conducted a demand response pilot with PG&E last year where Powerwalls provided 33 MW of energy back to the grid when needed (at the cost of an incredible $2/KWh).
The main question outstanding is when the cars themselves will support Vehicle to Grid. But even those can be adjusted via service centers and new deliveries.