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The price of solar power just fell 50% in 16 months

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Re: The price of solar power just fell 50% in 16 months

#341

Post by afarrell »

eru wrote: post #332
S_A_P wrote: post #229

Earlier quoted context omitted.

Can validate. The problem with electricity is that there is no large scale storage like there is for other forms of energy like NG and Crude. Until someone comes along and figures out how to store electricity, this will continue to cause grief to power companies. Power plants are really just options, if the price per kWh is at a certain point then it makes sense to spin up or take down a plant and generate power. Add…

Instead (or rather in addition) to storing power, we can also get better at coordinating demand. There are already programs for industrial users to get electricity for much cheaper, if they can tolerate power cuts during peak demand. Those programs will become more and more rewarding to join and extend and automate as supply gets spikier.

Is there a way to coordinate demand without asking thousands of people to give Alice the ability to shut off their appliances?

Re: The price of solar power just fell 50% in 16 months

#342

Post by serge2k »

coryfklein wrote: post #215
ChuckMcM wrote: post #103

The aggressiveness of the price drops on solar is pretty amazing. I just lost one of the inverters on my grid-tie system after it had run trouble free for 13 years. So we're looking at the first "major" repair to the system I installed in 2003. And in 2003 my 5.2kW of panels on my roof cost $38,000 before subsidies and $19,000 after. 28 panels, two 2.5kW inverters, net about 4.2kW of generation. I priced out replacin…

> And that is why it is a huge problem for the power companies It is a problem, but not necessarily in the way you may be thinking. Peak residential power usage is in the evening when solar isn't available. Power companies therefore end up spinning down coal and natural gas during peak solar, then just spinning them back up again as the sun begins to set. [1] So you haven't replaced the coal and natural gas plants, y…

This is why we need a major leap in battery tech to make solar more viable.

Plus there is the problems of cities with not enough sunshine and otherwise problematic weather (snow on the panels).

Re: The price of solar power just fell 50% in 16 months

#343

Post by kazagistar »

eru wrote: post #337
epistasis wrote: post #225

Earlier quoted context omitted.

Being a manager at a large power company for 30 years is both an advantage and a disadvantage. For the past 30 years, the energy industry has changed incredibly slowly, so ones expectations of what is possible in the way of innovation is far far lower than it should be. The "duck curve" that your friend is referring to will be solved in a variety of ways, from wind to storage to HVDC interconnects to the rest of the…

Nuclear could be made cheaper (even with Uranium) by updating regulations. Fission plants are held to a much higher standards of safety in terms of eg decrease in quality adjusted life-years per Gigawatthour than any other form of producing electricity. Even solar. (Though most deaths and injuries from solar come from people slipping off their roof when installing residential capacity. If memory serves right.)

The problem is they have a huge spinup and spindown cost. So as long as we have solar, we need power that we can use at those times when solar is unavailable.

Re: The price of solar power just fell 50% in 16 months

#344

Post by Spooky23 »

coryfklein wrote: post #215
ChuckMcM wrote: post #103

The aggressiveness of the price drops on solar is pretty amazing. I just lost one of the inverters on my grid-tie system after it had run trouble free for 13 years. So we're looking at the first "major" repair to the system I installed in 2003. And in 2003 my 5.2kW of panels on my roof cost $38,000 before subsidies and $19,000 after. 28 panels, two 2.5kW inverters, net about 4.2kW of generation. I priced out replacin…

> And that is why it is a huge problem for the power companies It is a problem, but not necessarily in the way you may be thinking. Peak residential power usage is in the evening when solar isn't available. Power companies therefore end up spinning down coal and natural gas during peak solar, then just spinning them back up again as the sun begins to set. [1] So you haven't replaced the coal and natural gas plants, y…

That's a good thing. Peak power usage is midday, so providing additional supply at that time avoids the need to site new plants, which costs millions or billions of dollars.

It also makes coal less economical and makes gas plants, which are cleaner and safer to operate more economical.

Re: The price of solar power just fell 50% in 16 months

#345

Post by DennisP »

eru wrote: post #332
S_A_P wrote: post #229

Earlier quoted context omitted.

Can validate. The problem with electricity is that there is no large scale storage like there is for other forms of energy like NG and Crude. Until someone comes along and figures out how to store electricity, this will continue to cause grief to power companies. Power plants are really just options, if the price per kWh is at a certain point then it makes sense to spin up or take down a plant and generate power. Add…

Instead (or rather in addition) to storing power, we can also get better at coordinating demand. There are already programs for industrial users to get electricity for much cheaper, if they can tolerate power cuts during peak demand. Those programs will become more and more rewarding to join and extend and automate as supply gets spikier.

That's great but then instead of increasing the effective capital cost of the generating plants, you're increasing the effective capital cost of the industrial facilities (by lengthening the time to pay off financing).

It'd be interesting to see a study comparing the two options.

Re: The price of solar power just fell 50% in 16 months

#346

Post by bjterry »

kragen wrote: post #194
gonzoflip wrote: post #179

Earlier quoted context omitted.

May I ask where you got your 3% because that number is very low compared to any number I have ever read? This Wikipedia chart shows annualized returns to be 10.47%. That is >3x your 3%. https://en.wikipedia.org/wiki/S%26P_500_Index#Annual_returns

3% is an estimate of the rate of economic growth: http://www.tradingeconomics.com/united-states/gdp-growth As I said above, we should expect the market's long-run returns to be close to the rate of economic growth. It's true that stocks in the US in the 20th century dramatically outperformed that 3%. This is for three reasons: first, up to about 1975, the world's economic growth rate was higher than 3%, due to the Se…

Returns to the S&P should beat GDP growth even in the long run, steady-state.

GDP growth flows to both debt and equity. The debt market is actually much larger than the equity market and since its returns are lower than equities, and they both share GDP as a source of returns in the long run, equities should beat GDP growth in the long run. This argument isn't iron clad, but hopefully you can see the general picture.

The Gordon growth formula is taught in intro to finance classes to estimate returns to equity. The theory is that stock market returns equal the dividend yield plus growth in stock prices. Stock prices alone are in the long run expected to grow at the same rate as GDP, but the actual return should be higher by the rate of the dividend yield.

These are the most basic arguments against what you're saying, but I would also caution against assuming that any particular macroeconomic trend will end, especially that it will end in a timeframe relevant to decisions related to solar panel installations. Sometimes they just keep going. There is no mathematical reason that equity prices can't go to infinity, as required rates of return can decrease to zero. If the world becomes more predictable and stable, equities can keep becoming more and more valuable with no damage to finance theory.

Re: The price of solar power just fell 50% in 16 months

#347

Post by DennisP »

ssmoot wrote: post #294
jobu wrote: post #262

Earlier quoted context omitted.

> When storing a kWh costs $0.10, and there's also adaptive pricing to match supply and demand better, these problems will melt away. If the math and assumptions in this article are correct, then that's exactly the (wholesale) price point Tesla is aiming for with the Powerwall: http://cleantechnica.com/2015/05/09/tesla-powerwall-powerblo... There are a couple other (not yet released) energy storage solutions mentione…

It'd take over 1 BILLION Powerwalls to store half the daily usage in the US (using old usage numbers off Wikipedia). I wonder if there's enough raw materials to make that realistic. And how to you manage recycling, repair, replacement, end-of-life concerns for all those batteries on that scale? Not asking a sarcastic hypothetical. Genuinely curious. It's hard to wrap my head around numbers that big. For reference I u…

Raw material supply is a big issue; see Berkeley physicist Tom Murphy's calculations: http://physics.ucsd.edu/do-the-math/2011/08/nation-sized-bat...

He's mainly talking about lead but for lithium it's even worse.

A lot of things look great until you look at the scaling limits. Hydro storage is another example; Murphy's got a post on that too.

Re: The price of solar power just fell 50% in 16 months

#348

Post by zaroth »

ssmoot wrote: post #330
toomuchtodo wrote: post #328

Earlier quoted context omitted.

Think about if Tesla vehicles were used instead of Powerwalls: https://i.imgur.com/oLBNeW4.png | https://i.imgur.com/pectzXn.png

Your car isn't at the house while solar is being produced though for many/most people right? This seems unrealistic.

I guess it could drive itself home after dropping its owner off at work, but that's probably too inefficient in most cases to make a full extra round-trip just to charge up with the panels at home.

Re: The price of solar power just fell 50% in 16 months

#349

Post by hinkley »

amenghra wrote: post #236
S_A_P wrote: post #229

Earlier quoted context omitted.

Can validate. The problem with electricity is that there is no large scale storage like there is for other forms of energy like NG and Crude. Until someone comes along and figures out how to store electricity, this will continue to cause grief to power companies. Power plants are really just options, if the price per kWh is at a certain point then it makes sense to spin up or take down a plant and generate power. Add…

Some countries store energy by pumping water up a dam. Seems efficient.

I thought I read that some water districts run their pumps at reduced volume during peak hours and top them off before or after. It's a smaller volume but it's already a solved problem.

And it allows you to push some levers and dials as to whether it's cheaper this year to increase your water capacity or your power capacity. City planners love that kind of thing.

Re: The price of solar power just fell 50% in 16 months

#350

Post by driverdan »

ryanmarsh wrote: post #316
warmwaffles wrote: post #107

Earlier quoted context omitted.

How long until you start seeing a return on investment? Right now my electricity bill for my home is ~100 a month in Texas. I would need to keep the same panels without maintenance fees for 33.33 years by your price point of 40k

$100 a month in the summer in Texas? You living in a shoe box in the panhandle or what? I spend $700 a month in August. Tell us your secret for real.

I live in TX and have never spent anywhere near $700/m on electric. Either you keep your AC at 65 or something is very wrong.
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