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Giant batteries and cheap solar power are shoving fossil fuels off the grid

sciencemag.org

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Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#181

Post by nimish »

litany wrote: post #158
rmuesi wrote: post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

So the thing is the economics of rooftop solar are a lot different than power station solar. The DOE has public data on how much utilities pay for electricity. In a market like mine, Southern California Edison isn’t an electricity generator, they buy power at about $0.02/kWh but then they sell it to the residential consumer for up to $0.32. So clearly it’s a very different calculation. Regardless of that generators a…

Because the powerwall allows you to "buy" power at the opportunity cost of $0.02/kWh vs paying up to $0.32/kWh ? If you end up generating a lot of excess solar using a lot of grid power at peak times, it could pay for itself.

But of course, you need to do the calculation for your situation.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#182

Post by codesushi42 »

kragen wrote: post #133
codesushi42 wrote: post #78

Earlier quoted context omitted.

That doesn't have to do with temperature, it has to do with the efficiency of the engine. Gas burns at a much higher energy than steam, so it's much easier to extract more energy with less fuel, making for a smaller form factor. I should clarify I was talking about an engine here. Not a power generator. What I said is correct though. You can compensate for lower temperatures with a more efficient engine & energy conv…

Neither the “engine”/“power generator” distinction you are attempting to make, not the statement “gas burns at a higher energy than steam”, is physically meaningful. It is true that supercritical steam turbines operate at a lower temperature than gas turbines, and if the cold reservoir of the Carnot engines in question were at the same temperature, that would indeed make gas turbines potentially more efficient. But i…

Thanks for taking the time to write this informative post. I am grateful that HN is home to real engineers. :)

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#183

Post by bluGill »

xyzzyz wrote: post #148
snarf21 wrote: post #116

Earlier quoted context omitted.

There are two data points you are missing. Land purchase and annual taxes add cost. To get to the scale of 1000 house, let's just pretend you need 100 acres. So where are you going to get that much land close to people so you cheaply transport it? Also, developers will make far more from that land near a suburban neighborhood than you can as a solar farm provider meaning you would have to overpay for the land. Most s…

So where are you going to get that much land close to people so you cheaply transport it? Why would you need the land to be close to people? Electricity transmission losses over 100-200 miles are minuscule, and there's plenty of cheap land in the radius of 100-200 miles from literally any point in the US.

cheap land can still be expensive. For the rooftop it is a sunk cost and so "free."

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#184

Post by mikemotherwell »

rossdavidh wrote: post #156

Good news: non-carbon energy sources will, faster than most of the world currently thinks, force carbon energy sources off the market. This has already started to happen with coal. Bad news: Well the Left may lament the fact that it will not be due to any change of heart or international cooperation, it will just be due to mercenary calculations of cost, and technology. But all of us have to consider what will (not m…

Is that actually true? I just can't believe it is, when there is no backup source of power for overcast/windless days. can you show that this is actually accurate?

I can see where places with bad power supply currently, with the rolling brown and blackouts, might move to renewables, especially if 1st world countries subsidize it. "Oh, these are flaky and power is intermittent? So business as usual?"

But is coal really being moved out in the 1st world? Still the largest source of power in Germany.

The pie chart here https://en.wikipedia.org/wiki/World_energy_consumption shows that over 54% of the world's energy came from carbon. AFAICT as primary energy, that excludes motor vehicles (the graph above has oil higher than coal). I'm not sure if a reduction of 10% from carbon sources would represent a decrease in total carbon, given the rate of growth of energy usage world wide which https://en.wikipedia.org/wiki/World_energy_consumption#/medi... demonstrates.

In any case, is it true that, globally, "non-carbon energy sources will, faster than most of the world currently thinks, force carbon energy sources off the market"?

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#185

Post by TheSpiceIsLife »

litany wrote: post #158
rmuesi wrote: post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

So the thing is the economics of rooftop solar are a lot different than power station solar. The DOE has public data on how much utilities pay for electricity. In a market like mine, Southern California Edison isn’t an electricity generator, they buy power at about $0.02/kWh but then they sell it to the residential consumer for up to $0.32. So clearly it’s a very different calculation. Regardless of that generators a…

> they buy power at about $0.02/kWh but then they sell it to the residential consumer for up to $0.32.

This is the most important factor in the whole discussion.

The electricity retailers, which consist of a call centre and a two billing systems, accounts payable and accounts receivable, buy electricity for virtually nothing, $1.00 buys them 50kWh, that's about double what my houses uses per day with two adults. edit to add: per day

I'm guessing the electricity retailers aren't making a lot of money after expenses, otherwise investors would flood the market.

How would a reduction in wholesale electricity price translate to a reduction in residential retail price given the wholesale price is already almost at zero.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#186

Post by driverdan »

darksaints wrote: post #46

I know someone who has gone fully off the grid via sailboat and is currently on his way around the world. He converted his sailboat to a hybrid setup (electric engines powered by the same batteries that power his stovetop, refrigerator, etc.). His power sources keeping those batteries charged are solar (1200W) and sail regeneration [0]. He has an 18kw diesel generator as a safety measure. His story is particularly in…

That's really cool. I like seeing other off grid solutions.

I live in a bus with 1800W of solar. I still burn a lot of diesel driving around but very rarely have to run a generator or plug in for electric, even when I run my AC.

I love being off the electric grid. There's something so satisfying about using electric power and knowing it incurs no additional negative environmental cost. I never think twice about using power, assuming I have enough available.

When I finally buy some real estate I'd love to be off grid but still have fiber internet. I don't think that'll happen but I can dream.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#187

Post by torpfactory »

nexuist wrote: post #118
DubiousPusher wrote: post #70

> the cost to decarbonize the U.S. grid alone would be $4.5 trillion They make this sound like a lot but that strikes me as actually pretty cheap. I don't think that number can be right. Edit: I mean seriously think. The F-35 has cost us 1.45 trillion dollars so far. That's roughly 1/3 of the price they're asserting here. Localizing our entire energy dependence has got to have some serious national security benefits.…

>Localizing our entire energy dependence has got to have some serious national security benefits It would also cause extreme instability by shooting up unemployment, destroying large corporations that offered valuable careers with good benefits, and exacerbate polarization between those who believe in man made climate change and those who don't. Don't get me wrong - I think energy independence is the way to go - but…

I imagine that it would take a fair number of new workers to help burn that $4.5T. They wouldn't work for oil companies, but they might still be involved in energy production.

Besides, it's not like we have some choice here. We can either decarbonize our world economy or perish. I'm awful sick of the 'but the jobs' arguments. We don't need jobs in outdated, polluting industries. That is outright theft of healthy ecosystems from future generations for short term gain, if you can call it that.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#188

Post by driverdan »

imtringued wrote: post #53
driverdan wrote: post #13

> In March, an analysis of more than 7000 global storage projects by Bloomberg New Energy Finance reported that the cost of utility-scale lithium-ion batteries had fallen by 76% since 2012, and by 35% in just the past 18 months, to $187 per MWh. I hate it when they list battery prices this way, it's very misleading. That's the amortized cost of $187 per MWh cycle, not the battery's upfront cost. Assuming 2000 cycles…

That isn't just misleading, it's completely wrong.

How is it wrong?

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#189

Post by cortesoft »

rmuesi wrote: post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

As others have pointed out, wholesale energy cost is only about $0.02 per KW/H, yet retail is usually over $0.2 KW/H.

Even if the wholesale cost of energy drops to $0, you are only dropping about 10% of the total cost of energy.

Of course, this brings up another interesting question that has been a hot button issue; if power companies are supplying less and less power (since more and more people are getting their own power from solar), the economic model of paying for power infrastructure by paying a premium for kw/hours isn't going to work. The infrastructure cost is fixed, even if everyone is generating their own power (assuming people still want to be connected to the grid, and even people with solar generally want that). How do we pay for that infrastructure?

Power companies have tried to introduce surcharges for solar users, but that has gotten a lot of pushback because it seems to be punishing people doing the right thing. However, the alternative is to push more of the cost onto non-solar users, which doesn't seem fair either, especially since solar users still get the benefits of the grid.

It is not an easy question to answer.

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