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Comment by aseerdbnarng | Hacker News Reader

> A lot of hyperbolic reporting but there’s a ton of off-peak excess overnight electricity capacity.

Looking at California's demand-profile it appears almost flat throughout the day (page 3 http://web.stanford.edu/group/efmh/jacobson/Articles/I/Combi...). I dont see an obvious reaon why other cities would follow a different profile, so no I dont think that assumption is correct. The problem is indeed cost, but more the cost of storing the energy created by green renwables to be used when the wind isnt blowing or the sun isnt shining. If anything electricity will become much more expensive and become cheaper not overnight but instead when the weather is great. Indeed this is whats happening in Germany as a result of their energiewende program

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> I dont see an obvious reaon why other cities would follow a different profile, so no I dont think that assumption is correct

A flat demand profile is definitely not normal. Do i really need to explain that the rest of the country doesn’t have same weather as California...

- California used as example due to high EV adoption - Here is a link containing the UK's daily load factor https://gridwatch.co.uk/ Its quite flat.

That’s a long way from a flat curve. 30GW to 50GW is a huge swing in demand.

That was only in July and only due to the high AC required. Are you planning on recharging only 1 month of the year? How good are your batteries and where can i get them?

Summer months in most of the southern US are extremely hot (in Austin, 4-5 months of the year could have temps above 100F), so for example here is CA in August (see graph in article for demand): https://www.greentechmedia.com/articles/read/how-californias...

Utilities can't design just for the average month, but the worst ones, and the worst hours of the worst days. Building new peak demand (peaker) plants is very expensive and most consumers probably don't see the actual market prices during those times. Shifting load by a very small percent could result in a decent cost savings and/or avoid building new capacity.

Smart grid is a buzzword but this is exactly what it's good for. Spreading peak usage out. For example, today I get a discount on my electric because my power company has the option to turn my AC off for X time during hot days to lower the grid's peak load. The tech is already here and a lot of EV charging will fit well into that model, especially commuters that don't need their whole range every day. Plenty of people would opt in to "at least one full charge every 3 days" type of plans.

In terms of capacity planning it’s the peak annual demand that’s critical not the peak seasonal demand. January is effectively a minimum of 24GW vs a capacity for 50 GW.

In practice it’s a little more complex as maintenance cycles for example are lined based on seasonal demand, but that’s offset by much higher transmission losses when the temperatures are highest.

But California does not have a 50gw generating capacity. It imports electricity during the summer months to make up the load factor difference. So again I’m not sure how you’re planning on recharging millions of vehicles without increasing the overall load factor if you’re relying on vanishingly small gaps in the load factor demand throughout the day

Sharing power also takes infrastructure, as existing long distance power transmission has limits which cost money to maintain or increase.

Really, the US electric grid is designed to share power between states, that’s just part of capacity planning. Further, sharing power is a cost saving measure and happens as soon as importing power costs less than using a peaking power plant. It still requires someone to have built the generating capacity, but it’s much easier to add 1GW of base load capacity at a time when your selling some of that to a different state.

As to minor differences 50GW is 67% larger than 30 GW that’s a huge swing over the course of a day. At 0.5 KW per person in CA x 4 miles per kWh x 12 hours x 365 days, that’s 8,760 miles per year which is almost enough on it’s own. Suggesting at most a minimal capacity increase.

Does California build extra infrastructure during summer and tears it down during winter, or why would the grid be unable to manage summer's peak demand during winter?

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