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Comment by milcron | Hacker News Reader

Electricity isn't a great market. End-users with solar power are allowed to use the grid as a perfectly free battery, which is why everyone is dumping power on the grid at high noon.

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Where I live its about 25c (of Australian Dollar) for 1kwh but you only get 7c back. So a real battery would be much preferable.

Due to subsidies, in the US people dumping home solar into the grid usually get back more than the market rate.

I don't think that's the case. Depending on where you are, you either get paid retail or wholesale rates, and still have to pay some monthly service fee regardless of surplus or deficit. I've never heard of any utility in the US buying solar production at more than retail rates.

> I've never heard of any utility in the US buying solar production at more than retail rates.

That doesn't refute the parent's claim of it being greater than the market rate. The residential retail rate [1] usually doesn't change, except on a long time scale, after regulatory approval, while the market rate changes intra-day, based on supply and demand.

If peak sun doesn't correspond to peak demand (and, from what I've read, it doesn't), those periods are where the utility could be taking a huge loss. For example, if PG&E has a customer in the top marginal usage tier is "selling" power at 25c/kWh when the wholesale market is selling it at 4c, that's a pretty tremendous loss.

[1] Often not even a single rate but a tiered one, so a heavy residential user could be "selling back" power at a particularly high retail rate, much higher than average.

> you either get paid retail or wholesale rates

So above market rates. Sorry, your 10kw of intermittent unreliable power provided at your whim into a random neighborhood grid is not worth the same amount per kwh as reliable base/load following generation. And that's wholesale.

Retail priced net zero metering is even worse - that's simply poor people subsidizing rich folks with solar panels.

Maybe the subsidization is ok overall due to the system changes it (might) bring about - but man it's bothered me for decades that rich folks who can afford to blow $25k+ on solar installs act so smug about net-metering - when it's them simply stealing from other ratepayers for their free battery.

> Where I live its about 25c (of Australian Dollar) for 1kwh but you only get 7c back

I've read about places that don't actually do "net metering" and implement this with two separate meters, one for inflow and one for outflow.

Is that the case where you are? Are there any time-of-use options available that might sweeten the deal?

> So a real battery would be much preferable.

Assuming it were free (even to purchase, with only charge/inverter efficiency losses), of course it would. However, as much of the discussion in the thread points out, storage is very capital (if not maintenance) intensive, even at utility scale.

It doesn't need two meters, you can just keep separate track of the times that the connection is a net exporter and the times it is a net importer.

That's true, in that, if the metering is purely electronic, the only thing "separate" would be two different readouts. For electro-mechanical metering, I'd still expect a need for two physically separate ones.

Regardless, substituting "readouts" for "meters" is irrelevant to my question.

Its a single digital meter.

For a few weeks we had the old style meter. It span backwards on a sunny day. So for that time period it was same rate in and out.

End-users who produce electricity aren‘t a problem for the grid, they produce electricity very close to where it‘s mostly consumed (typically they consume most of it themselves). Wind farms on the other hand are built where it‘s cheapest and yields are best, often far away from any relevant consumers.

With their own batteries for 24h+ (soon...), end-users will be the best thing that can happen to the grid.

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