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Comment by JoeAltmaier | Hacker News Reader

Rooftop solar would have a very hard time supplying the same current feed your power company has. A few back-to-nature Californians may be satisfied with the battery-solar combo straw man in this article; most of us want our TV and microwave too.

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Really - I am not so sure... my brother in CA tells me after installing solar panels on his home his bill from the power company went from 3 digits to $4 per month. He isn't really a back-to-nature Californian either...

Maybe we need 200 Amps from the power company for peak demand (frozen pizza + ball game + blender) but don't really pull much most of the time. Batteries limit not peak but total draw over the day. Hm.

200 amps even at the ultra low voltage the US has is still 20 kilowatts. That is tumble drier, oven with stove tops, washing machine + everything else in the house and you still have 10 kilowatts to spare.

Also chances are pretty good not everyone will have everything going at the same time, so you would be able to borrow power from your neighbours' systems without needing a big utility with standby coal.

Heat based energy needs are usually cheaper with gas, which is most of what you listed.

The threat isn't that people don't need any power from the electric company, it's that people need very little of it. Demand dropping to 5% of your usual business model might as well be demand dropping to 0%.

Especially when you're dealing with physical infrastructure (like power lines) that has relatively fixed upkeep costs regardless of demand.

Here in NYC ConEd charges a very large fixed fee for that physical infrastructure. Last month I used 96kWh but paid $43.35 (basically $0.45/kwh).

Around $20 of that is fixed fees, to pay for the basic infrastructure, billing, meter reading etc...

Some of that drop can be beneficial to the power company. They are always on the edge of capacity, because building more capacity is very (billions) expensive, and at first you don't need all of it, so the marginal cost of expansion is huge. Deploying solar across the area could postpone the need for generator expansion, and save money for current customers.

Depends on the type of capacity. I gather that peaking power is typically provided by gas combustion turbines (https://en.wikipedia.org/wiki/Gas_turbine#Industrial_gas_tur...), which have much lower capital costs and much higher operating costs (including maintenance). But if you need more baseline, then, yeah, you're going to be spending a lot of money, although I'd expect modern gas powered baseline plants to be relatively cheap (don't ask about nuclear, and fuel handling is much easier than coal, plus coal is nasty dirty stuff that needs exhaust cleaning, and disposal of ash).

I think Joe might have been referring to transmission and switching costs. Adding generation capacity to the grid usually means that you need more substations, and control infrastructure.

But in that case you can downsize a lot, because you only need to produce 10% of the normal electricity, and then charge, say, twice the amount your normally charge for the usage, perhaps reducing it to 8% or so.

That is still a higher rate of return than you would normally get, which makes it a better investment.

The batteries that Tesla uses can far, far surpass what a power company would be willing to provide to a residential unit.

The most powerful model s on the road right now has a ~310kW motor in it. That is an order of magnitude above what most house circuit breakers are rated for (200A-300A, 24kW to 36kW). There are even small RC batteries out there that can push 150A+ for a few seconds on their own.

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