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Comment by anonu | Hacker News Reader

We had solar-thermal panels on the roof of our house in Beirut in 1995... they're still going strong - just need to wipe them of dust every now and then. Hands down one of the best home appliance investments - especially in a country where electricity is sporadic.

The reason they haven't picked up in the US is because infrastructure is good - electricity delivery is reliable. It's much cheaper to install an electrical or gas water heater rather than the complicated plumbing needed to add solar-thermal.

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IIUC investing in PV is actually more efficient for heating/cooling than solar-thermal, because you can use them to run a heat pump, and heat pumps have something like 400% efficiency (i.e. with 1 kWh of electricity they can pump 4 kWh of heat).

Here in the Netherlands government is now trying to ramp down PV subsidies, because PV has been so wildly successful that electricity spot prices are actually negative at peak sun (midday). (Even without subsidies I believe the panels are now cheap enough to be worth the investment, though.)

> Here in the Netherlands government is now trying to ramp down PV subsidies, because PV has been so wildly successful that electricity spot prices are actually negative at peak sun

Which means people should start buying batteries. Pull in power during midday at a profit, and then send it back out in the evening at a profit. I'm curious how long it'd take to pay back the price of a battery.

I just a few days ago watched a really good fairly deep dive video about the US' historical reasons behind this:

https://youtu.be/fAyY0kGmgmc

Pretty much. All in all they’ve been a very poor investment for home owners in America. At best you break even after ~20 years if they’re even still functional.

Could change as tech improves but as of today they are pointless for most people.

> At best you break even after ~20 years if they’re even still functional.

This is misinformation.

I searched on google, bing and Yandex and all the results I found implied that breakeven would occur substantially before 20 years. The lowest breakeven time figure I found quoted was 5 years. The usual quoted breakeven ranges were, I'd say, 6-12.

You’re talking about PV, not solar thermal. Break even for solar thermal can be one year.

Even for PV, most payback periods are under 10 years at this point. In sunnier areas payback periods can be just a few years.

Source?

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