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That's terrible advice unless it's tied to local energy storage. When every roof and every solar panel is angled the same way, a sudden cloud (or a sudden lack of clouds) can cause huge fluctuations in power output. Diversity is protective.
Are you signing up to point your panels north and take a 30% efficiency hit? Or east/west for a 15% penalty? People point them south because it's the most efficient fixed orientation north of the equator. A more efficient solution is to use a tracker which keeps them pointing directly at the sun as it traverses the sky.
A battery helps negate this issue but not entirely.
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Sounds like a rare case of America's ubiquitous suburbs working out for the environment. Everyone has a "roof" that gets sunlight most of the day, so rooftop solar, while being less efficient, is still a viable candidate. (Although, if you factor out all the extra driving needed for the suburban life, it would likely still come out negative compared to a proper city.)
Yeah, don’t over look the fact that the thermal demand from space conditioning homes is way higher on a per capita basis in a suburban context compared to an urban context with multi-family housing/apartments etc. There’s just way more air volume to condition per person, generally more inefficient systems, etc.
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Grid connected solar goes down when the grid is out though. You need specific inverters to retain power. You also just have issues like the low chance of having clear skies after a hurricane or a bushfire. For disaster situation power, a diesel generator is still the cheapest and most reliable option.
Sure, but that's why my emphasis was on distributed grids . Interlinking local capacity / having one or two neighbors with fully fledged systems is way better than going weeks charging stuff in your car. When you're without power for weeks, you'll probably have enough sun for more than enough days to get yourself sorted. Hurricanes also tend to sweep up any other systems in the region, so once they disperse, it's pre…
Is this a thing IRL? Every system I've looked at stops feeding the grid as soon as the grid goes down
Earlier quoted context omitted.
Yeah, don’t over look the fact that the thermal demand from space conditioning homes is way higher on a per capita basis in a suburban context compared to an urban context with multi-family housing/apartments etc. There’s just way more air volume to condition per person, generally more inefficient systems, etc.
Even for the same amount of living space, apartments are way more efficient. A typical apartment unit is surrounded by other units up/down/left/right, so only two sides are exposed to outside air. A single house is exposed on five sides.
Six. The most heat escapes through the roof, but thermal loss through the floor is generally about 10-15% of the total.
Earlier quoted context omitted.
Sure, but that's why my emphasis was on distributed grids . Interlinking local capacity / having one or two neighbors with fully fledged systems is way better than going weeks charging stuff in your car. When you're without power for weeks, you'll probably have enough sun for more than enough days to get yourself sorted. Hurricanes also tend to sweep up any other systems in the region, so once they disperse, it's pre…
> Interlinking local capacity Is this a thing IRL? Every system I've looked at stops feeding the grid as soon as the grid goes down
But that's more a policy decision than a technical restriction. We could change it so power can flow on both sides of a fault instead of only the "upstream" grid side.
This is a very impressive refinement of their existing tool, but is this type of advanced calculation of roof-pitch (etc.) still relevant? Haven't we more or less concluded that a million piecemeal rooftop installations of solar are about the worst way to do it? More complicated and expensive to permit and install, less efficient operation, difficult to repair, difficult to insure, difficult to upgrade, inefficient t…
I’m amazed at the amount of opposition to centralized solar generation. I assume there’s a fair bit of fossil fuel industry astroturfing involved.
Estimate for a house in SF with a typical roof and typical electric bill. $20k upfront cost. $4k in savings over 20 years. That's an implied rate of return of 0.9% annually. No thanks.
i've heard of some business models that install these and have you pay what would be the difference to your electric bill to the company until they pay themselves off, not sure if the panels last long enough to make that work though
A lot of the time such companies pray on people on stupid plans (or those paying thru the nose for "exclusively renewable") power.
Builders: optimize energy capture, put roof planes directed south (in northern hemisphere).
That's terrible advice unless it's tied to local energy storage. When every roof and every solar panel is angled the same way, a sudden cloud (or a sudden lack of clouds) can cause huge fluctuations in power output. Diversity is protective.