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Comment by jcampbell1 | Hacker News Reader

I have never understood residential solar. Seems like a gimmick. Why would I want these panels on my roof? It seems like hosting a server in your basement. It is appealing in theory, but silly in practice. If I just hosted my panels at a site where other people hosted their solar panels, you could probably install it for less than $1.00 per watt.

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Well for one, in some parts of the country residential solar means a $0/mo electric bills and in somes cases you spin the meter in reverse and build a credit. The panels themselves are maintenance-free, have 20-30 year warranties and (personally) just look plain cool.

I have a family member who has a large array on his roof and he runs his entire house and charges his Tesla all off the grid. He's still connected, but in most cases he runs a $0 bill.

I think jcampbell1's point is why bother putting the pannels on top of your own roof? Instead, buy your pannels on some other shared property that is already connected to the grid, and share the overhead costs. The same power would be sold back to the grid and offset your own home's power. I call this the co-op model, and I think it's also appealing for areas where not everyone is a home-owner.

It turns a surface that mostly transfers heat into your attic into a surface that transfers less heat into your attic and a great deal of electricity into your house during the part of the day that requires the most air conditioning.

If you live anywhere that's hot much of the year, it's a great deal, dropping your electric bill precipitously and recouping costs often in 2-4 years in that type of situation (as opposed to 7-12 in less reasonable areas). Also due to the nature of how cheap the electricity is during the day, you can set the A/C low during the day "coast" off the temperature differential during the night closer to a temperature you'd like.

Bad areas for solar: Constant cloud cover, Lots of overhanging Trees, far northern latitude. I would not use it in Alaska, Portland or Atlanta for these reasons.

Wait Atlanta? I was with you until you hit an incredibly hot city with a therefore powerful sun.

Atlanta is FILLED with very tall trees. Which then fall on your panels and break them.

https://maps.google.com/maps?q=google+maps+atlanta&hl=en...

Those large green trees? They're 60-160 feet tall. Drop branches every severe wind. There all over the place (Although most are under a hundred feet tall). They knock out our power lines, our cable lines and when they fall, our houses (luckily most people remove them long before that point).

There are certainly suburban areas near Atlanta where they've been clear cut in their past as part of their transformation into chicken farms (Before being turned into housing), and those locations would likely be EXCELLENT areas for solar panels.

But anywhere that has original trees, nope.

There may be advantages if you are using it to run an air conditioner somewhere sunny. Peak output will sync up to peak usage, and you won't need to take the losses stepping it up and down for distribution.

There might be a bit of conspicuous environmentalism, but it's probably mostly about permitting and property rights issues. No one would lease you the roof for $50/month so that you can install panels over them, but they'll happily install their own.

This is something that's allowed for in some solar regulations, using a system called Virtual Net Metering. It works the same way as normal net metering (where power sent back into the grid runs your meter backward), except that the power output can be allocated over multiple people's electric bills. IIRC, there are community solar projects that do exactly what you describe.

http://www.cpuc.ca.gov/PUC/energy/DistGen/vnm.htm

Thanks for sharing the link. Virtual Net Metering looks interesting. That particular regulation sounds like it is designed for a multi-tenant use case, and the panels must still be on site. It would be nice if Virtual Net Metering was available even if my panels were co-located at some muni site.

You can use otherwise unused space - that's the theory. Now if you install solar heating panels on your roof you can actually heat your house and warm your water with that, even in winter. They're fairly efficient. Nobody does that in germany though, since it's more economical to sell the power generated by solar panels.

Heating panels are also simpler and cheaper then the eletricity generating ones.

That's exactly what's happening in some places in Vermont. (I know, not the first place you think of when you hear 'solar.') People can buy shares of a solar co-op and get credited on their power bill for their portion of any electricity generated. It will be interesting to see how that model works in the long run.

In the UK, energy used in homes accounts for more than a quarter of all national energy use and carbon dioxide emissions. Space heating consumes the largest amount of energy for most households. An alternative to solar panels is simply better insulation for housing. This can dramatically cut energy consumption.

BTW, Germany has been a pioneer in this regard too as it developed the PassivHaus standard for energy efficiency in buildings. The standard is over a decade old and it's been demonstrated that existing or older housing stock can also be retrofitted to meet the standard (although it can be expensive).

But even without the rigour of the PassiveHaus standard, there are many other techniques to substantially improve the insulation of existing buildings so their energy costs shrink. To me, it seems sensible to think about reducing our energy consumption as well as finding alternative, cleaner (greener) technologies.

Well, proper insulation of houses has been standard for many decades in properly developed countries. UK is kinda infamous over here for not knowing how to insulate.

Examplified in this joke: 'Why do Englishmen put their pipes on the outside of the house? - Because it is simpler to exchange them when they freeze.'

/Swede

Real estate: if data centers could not stack servers vertically I imagine there'd be a business to renting out rooms in your homes to Google!

Also transmission to places where real estate is cheap is costlier than you'd think, largely due to red tape.

What else is your roof doing during the day if it is not raining? In the hotter areas of the US, covering your roof in solar panels not only generates electricity, but reduces attic temps and the need for A/C.

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