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Cheap Solar Power

keith.seas.harvard.edu

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Re: Cheap Solar Power

#71

Post by djrogers »

I really have to take exception with a statement in the opening here:

> rooftop solar seem systems which are (arguably) little more than green bling for the wealthy

My rooftop solar system (installed in late 2013) is 2.5 years in to what is looking to be a 5.9 year break-even point. After 6 years I will be earning $4-5k/year from it. Even if I had financed this (not a solar lease, those are usually structured so the leasing company gets all the benefits) at a high interest rate, it would turn out to be one of my best investments on a $/return basis.

The fact that basically don't have a monthly power bill (which is substantial in hot parts of PG&E land) is my #1 benefit here, as reducing my monthly budget by that amount makes the rest of my life that much nicer. The fact that I have reduced my 'carbon footprint' is barely on my radar compared to the financial benefits here....

I did find it crazy that the installer/designer wanted to know if I wanted more visible colors, or a portion of the panels facing the from top the house so they were more noticeable. I suppose some people just have to green-signal...

Re: Cheap Solar Power

#72

Post by dang »

Submitters: Please don't editorialize titles when submitting stories. The HN guidelines ask you to use the original title unless it is misleading or linkbait.

https://news.ycombinator.com/newsguidelines.html

(Submitted title was "Harvard Physicist, Long-Time Solar Skeptic Admits Solar Power Now Makes Sense".)

Re: Cheap Solar Power

#73

Post by ck2 »

Imagine an earth 1000 years from now where countries on one side of the planet help out the other side via solar power through superconducting power cables that have little power loss over 10,000 miles.

Since each side gets sunlight somewhere, no batteries needed. Of course 1000 years from now they could solve the battery problem too where each residence has its own low cost, safe storage.

Or 1000 years from now terrorists dirty-bomb everyone. Sigh.

Re: Cheap Solar Power

#74

Post by mrb »

tvchurch wrote: post #2

"Admits" seems a bit harsh, like he was doing his best to hide something from the world. By all accounts, it looks like he had written out a reasonable explanation as to why he predicted solar would not become cost effective. At the end of the day, if something doesn't make financial sense, it won't last long without subsidies from the government. The assumptions behind his predictions changed and therefore so did th…

"it won't last long without subsidies from the government"

This is a fantastic example of how government subsidies can help. Had there been no subsidies, the demand for solar power would have been smaller, the industry would not have been compelled to compete that much on improving solar power, and this Harvard researcher's prediction (solar not cheap enough in the near future) might have turned true.

He said these subsidies make no sense because solar is far from being competitive, yet they are the very reason solar became competitive.

Re: Cheap Solar Power

#75

Post by thrownaway2424 »

pilom wrote: post #58
thrownaway2424 wrote: post #39

When will this "duck pricing" actually trickle down to consumers? I'm on a PG&E rate plan that charges me an incredible $0.75/kWh during the afternoons of selected days. According to the figures in the CAISO paper, these are the hours of least net demand.

The CAISO paper looked at January and March. In the summer when air conditioners come on, the graph would have no dip and afternoons become the peak rather than evenings.

Ah, that makes some sense. Still, doesn't solar hack the top off that afternoon peak in the summer?

Re: Cheap Solar Power

#76

Post by thrownaway2424 »

beat wrote: post #35
amalantony06 wrote: post #27

Given that Solar power is the fundamental source of energy leading to petroleum based energy (starting with photosynthesis), it's surprising that we still rely on petroleum to the degree we do today. In 100 years this would perhaps be something people would find shocking (like how we are shocked today at how mainstream slavery used to be 150 odd years ago). Solar Energy is unlimited, cheap and clean. My guess would b…

150 years ago, slavery was much more economically viable - a lot of industrial-scale farming and mining was still purely manual labor. Machinery replaced most of the jobs once done by slaves. Likewise, for the past century or more, fossil fuels were the cheapest source of concentrated energy by far. That's about to stop.

That's an interesting interpretation. Historically didn't mechanization increase the demand for slaves? The relevant example would be the demand for slaves in the American south after the invention of the cotton gin.

Re: Cheap Solar Power

#77

Post by thrownaway2424 »

mjevans wrote: post #64
amalantony06 wrote: post #27

Given that Solar power is the fundamental source of energy leading to petroleum based energy (starting with photosynthesis), it's surprising that we still rely on petroleum to the degree we do today. In 100 years this would perhaps be something people would find shocking (like how we are shocked today at how mainstream slavery used to be 150 odd years ago). Solar Energy is unlimited, cheap and clean. My guess would b…

It is not unlimited. At the radius from the sun that our planet is, there is an upper limit to solar energy of about 4/3 Watts/(M^2) (projected across the curve of the earth during daylight... through atmosphere...) https://en.wikipedia.org/wiki/Sunlight#Intensity_in_the_Sola... The most effective way of collecting sunlight is to use curved reflective surfaces and concentrate it on to points that generate useful work…

Did you mean 4/3 kilowatts?

Re: Cheap Solar Power

#78

Post by beat »

epistasis wrote: post #48
beat wrote: post #26

Earlier quoted context omitted.

Cost. Synthetic fuels are very expensive. The ethanol industry sucks - it's just a fancy crop subsidy.

That's a biofuel, not a synthetic fuel. The difference being biological process versus a chemical synthesis process. BTW, I accidentally downvoted you, did not mean to! Sorry for the loss of an internet point. It wasn't mean to discourage your comment.

Synthetic fuels have it even worse, I think, in terms of cost. Unless we can get a really cheap form of electricity that is clean (solar) and connect it to a process that it more efficient than simply growing corn (or other biomass), then synthetic fuels will have the same problem. They can't be cost-competitive with fossil fuels without massive subsidy.

Re: Cheap Solar Power

#79

Post by jernfrost »

So year after year it is becoming evident that solar is the future and yet very little seems to happen elsewhere to accommodate this. Solar cells produce DC. Batteries which can store the solar power uses DC. Our iPhones, laptops, flat screens, electric cars use DC. Yet the connection between this DC power production and DC power consumption happens with an AC line wasting power.

It is also a dumb line. Solar power production varies considerably and a lot of power consumption is flexible but we don't have any intelligence built into the power distribution network to be able to tell devices when to use power and when not to.

Imagine if smart cables went into our laptops so they could charge when power was abundant/cheap and use battery when it wasn't. Electric cars could automatically start charging when power was cheap and stop when it got expensive. Washing machines could have timer function which would start them as soon as power prices were low.

Re: Cheap Solar Power

#80

Post by beat »

thrownaway2424 wrote: post #76
beat wrote: post #35

Earlier quoted context omitted.

150 years ago, slavery was much more economically viable - a lot of industrial-scale farming and mining was still purely manual labor. Machinery replaced most of the jobs once done by slaves. Likewise, for the past century or more, fossil fuels were the cheapest source of concentrated energy by far. That's about to stop.

That's an interesting interpretation. Historically didn't mechanization increase the demand for slaves? The relevant example would be the demand for slaves in the American south after the invention of the cotton gin.

The cotton gin is what made a large-scale cotton industry viable at all. Picking seeds out by hand is so labor-intensive that cotton clothing was an absurdly expensive luxury before that.

But really, the growth of the South during the first half of the 19th century was largely due to immigration patterns. The plantation owner class was largely already-wealthy men from the British merchant class. Due to British class structure, they could never equal even the poorest, lowliest members of the aristocracy, despite their obvious superiority. Moving to America gave them a chance to treat business acumen and wealth itself as an elite class. Next down the list were the scots-irish indentured servants, mostly rebels and criminals and their families. England could either hang them, or sell them to the plantation owners to work off their fines and immigration costs. They provided supervision over the slaves. The slaves were brought over to meet growing labor demand. So it wasn't so much new tech as the colonization and working of large tracts of previously wild land. (Remember, slaves were brought from Africa around the same time to work the sugar plantations of the Caribbean as well - the economics were compelling)

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