"electricity is only subsidized when the local jurisdiction is creating more of it than it needs anyway?" is false - there are a few cases of negative spot prices, which nonindustrial customers can't get, but all the rest of the time electricity subsidies are for economic and social reasons.

Normally surplus electricity results in a curtailment of fossil sources.

There is no such thing as "excess electricity". If that power wasn't being wasted on useless cryptocurrencies, then we could have used it for useful purposes, such as processing aluminum.

> no such thing as "excess electricity"

there absolutely is a disbalance between energy produced and energy consumed. if we're lucky, there will be storage capacity nearby. we're mostly not lucky. ever heard of australia? or tesla? google some.

> wasted on useless cryptocurrencies

yeah, transferring value securely without trusting third parties is not useful at all. gotta run all those banks and employ all those bankers, because that costs no energy nor other resources.

are you a banker by any chance?

If anything, crypto currencies will create more work for bankers.

Water power generated electricity

The Energy Waste Fallacy: https://github.com/libbitcoin/libbitcoin/wiki/Energy-Waste-F...

That argument makes no sense to me. It essentially boils down to "people can choose whatever level of security they want, so given that they chose the current level of security that must be the most energy efficient -- and since merchants have to pay for this system they always choose the cheapest fees which must therefore mean they choose the miner with the cheapest energy source". I'm not sure what this argument is meant to prove other than PoW chooses the most energy efficient way of doing PoW, but it doesn't prove the PoW isn't an energy hog.

This argument also explicitly ignores schemes such as PoS that don't have this massive power drain, and also ignores interesting schemes like PoC (Proof of Capacity)[1] that also don't have this power drain (apparently).

[1]: https://www.burst-coin.org/proof-of-capacity

I’m not going to spend a bunch of time reading this particular whitepaper, but not one of the three proof-of-capacity “mining” systems I’ve looked at are Sybil resistant and decentralized.

That's simply not true. When supply outstrips demand it's generally going to waste anyway.

Doesn't California actually pay Arizona to offload their surplus energy?

A few extra sunny days each year, due to lots of solar plants. Overall California imports more electricity than it generates in solar though:

http://www.energy.ca.gov/almanac/electricity_data/total_syst...

So the extra there is not really electricity you'd want to plan a crytocurrency operation around.

When supply outstrips demand in the power grid, the power is either sold elsewhere or you start shutting down plants.

Otherwise you'd ruin a lot of machines depending on either 220V/110V or 50Hz being on the grid.

If a hydroelectric power station produces 30 TWh per year, but demand including aluminum smelters is only 20 TWh, then there's 10 TWh excess.

This is use-it-or-lose-it. Should they just allow the river to flow and bypass the turbines?

This is a vast oversimplification, which only sounds plausible if you pretend that energy production scales linearly with demand. In the real world, if there's a plant producing more than its consumers demand, the reason for the excess capacity is to accommodate spikes and future growth. If you come along and build a BTC mining rig next door, that "future growth" has arrived sooner than expected, forcing the utility to build new capacity years ahead of schedule (presuming it's feasible to build it at all), resulting in significant price increases, their refusal to sell you as much electricity as you want to buy, or both.

The (amortized) cost of building out new supply is a major[0] part of the cost of electricity - this is why most big energy producers spend millions of dollars per year on energy efficiency incentives. Haven't you ever wondered why your power company will give you a $50 rebate on an EnergyStar dishwasher? Isn't it counter-intuitive that they would pay you to buy less energy, when they have excess? It's not because they're tree-huggers - it's because decreasing demand growth delays the day when they need to build a new plant to meet demand, which increases the profitability of the current plant enough to make those incentives cost-effective[1].

0: I can't find a good estimate and it varies by fuel type, but I rememeber an environmental engineer at a former job telling me it was about half. Look up "Levelized Cost of Electricity" for more info.

1: If you're not convinced, instead of demanding more details, I urge you to just stop and ask whether the proposition "There is a lot of excess energy production lying around which BTC miners can soak up without impacting everyone else very much" really passes the sniff test.

Hydroelectric is one of the oldest electrical storage systems there is -- you can store more electricity as gravitational energy by pumping the water back uphill, and then letting it flow back down during peak times.

There's a reason why hydroelectric plants and dams go together.

Very few dams have the capacity to pump water back uphill.

And they don't need it, because power-generating dams are generally only built in places that provide lots of downstream flow naturally, like the U.S. Pacific Northwest, or in places where a reservoir is already desired for other reasons (typically drinking water, navigation, and/or flood control).

Dams have the capacity to route downstream flow around some turbines to lower their generating capacity. It's not really accurate to think of that routed water as "wasted capacity," because that water would flow naturally even if the dam wasn't there.

... that reason being that dams are used to collect the water from rainfall.

With massive regional grids like what's present in North America, it's not just as simple as that. Someone on the other side of the continent could use your 10TWh excess and curtail their own fossil fuel use instead.

No, they can store it in some Tesla batteries.