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Satellite powered estimation of global solar potential

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Re: Satellite powered estimation of global solar potential

#181
post #44

Earlier quoted context omitted.

As someone who recently lost power and water for weeks post Helene, do not discount the power of distributed grids. Distributed core infrastructure will make for much better climate resilience. Don't miss this in your efficiency calculations.

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.

Not if you have a battery system attached

Re: Satellite powered estimation of global solar potential

#182
post #12

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…

Depends on your cost of electricity. In most places, a solar setup pays for itself long before the warranty runs out max 5-10 years typically (depending on a lot of factors). Even in the US which has a lot of extra cost related to people making things needlessly complicated and costly, lots of people are installing solar and earning their money back. I can actually get balcony solar here in Germany for about 240 euro…

Balcony solar sounds brilliant and probably has clear ROI. Rooftop solar is an awkward middle between grid-scale solar and balcony solar. Rooftop solar might only make sense in developed countries through subsidies.

Re: Satellite powered estimation of global solar potential

#183
post #12

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…

The majority of the cost of electricity in most jurisdictions is distribution, not generation. Grid-solar still requires distribution, so it is always going to have significant cost even if the cost of generation is insignificant.

If it can remove the need for a grid-tie, then rooftop solar can be significantly cheaper and more efficient. Can be, but isn't yet, because enough overcapacity and storage to eliminate the need for a grid tie is still too expensive.

Re: Satellite powered estimation of global solar potential

#184
I used an early version of the PV roof tool in 2020 for my own PV roof design. The front of my rectangle shaped home faces exactly North and therefore all sides are respective to exactly E/W/S. Given my professional experiences and knowledge awareness of photons I therefore opted to cover my entire roof in PV collecting technology and not just what faces direct sunlight, if one can see outside during daylight hours then the PV is functioning. Case in point, right now it is currently very cloudy and rainy here in the NE,USA and the roof is still generating 700 watts while my home's base load demand of 400 watts has the overage of 300 watts going to batteries. I have had this system for 3 years now and my choice to have such a system proved itself in our first outage when everyone else was panicking in the dark for hours. I sat relaxed and watched others in great stress and anxiety planning on how to preserve their refrig/freezers while visually panicking over their sump pumps not running in their basements. PV with a battery is a quality of life choice that directly impacts one's health and what price do you put on your health? I will also share with such sites that the energy and cost saving estimates are very much often wrong since the energy data is generalized for everyone and energy use per person significantly varies, some estimates are laughable to only me since I have my families own real world data for the last decade. I have also tracked our entire resource consumption at home for nearly a decade now, yes I am a data nerd to the extremes, and not only does such a solution save one GREAT stress and anxiety when it matters most but it also greatly reduces variable financial expenses and can also make one revenue.

Proactive versus reactive : The data doesn't lie, people do.

Stay Healthy!

Re: Satellite powered estimation of global solar potential

#185

I used an early version of the PV roof tool in 2020 for my own PV roof design. The front of my rectangle shaped home faces exactly North and therefore all sides are respective to exactly E/W/S. Given my professional experiences and knowledge awareness of photons I therefore opted to cover my entire roof in PV collecting technology and not just what faces direct sunlight, if one can see outside during daylight hours t…

> sat relaxed and watched others in great stress and anxiety planning on how to preserve their refrig/freezers while visually panicking over their sump pumps not running in their basements.

I hope you at least offered to help...

Re: Satellite powered estimation of global solar potential

#186
post #12

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…

The majority of the cost of electricity in most jurisdictions is distribution, not generation. Grid-solar still requires distribution, so it is always going to have significant cost even if the cost of generation is insignificant. If it can remove the need for a grid-tie, then rooftop solar can be significantly cheaper and more efficient. Can be, but isn't yet, because enough overcapacity and storage to eliminate the…

This is exactly the challenge. Here in California wholesale solar plant sell power for 0.03-0.04 kwh. Cost at the meter is 0.45/kwh.

Rooftop is competitive with the meter price, but unless you can cut the cord entirely, connection fees and rates will just keep increasing proportionally

Re: Satellite powered estimation of global solar potential

#187

I used an early version of the PV roof tool in 2020 for my own PV roof design. The front of my rectangle shaped home faces exactly North and therefore all sides are respective to exactly E/W/S. Given my professional experiences and knowledge awareness of photons I therefore opted to cover my entire roof in PV collecting technology and not just what faces direct sunlight, if one can see outside during daylight hours t…

> sat relaxed and watched others in great stress and anxiety planning on how to preserve their refrig/freezers while visually panicking over their sump pumps not running in their basements. I hope you at least offered to help...

Yes, I did mention this in closing: "can also make one revenue."

Re: Satellite powered estimation of global solar potential

#188
post #123
post #12

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…

Australia manages to install rooftop solar at well under half the cost the USA does (most of that is soft costs) and integrate large amounts of it into the grid. As of lunchtime today, nearly 50% of all electrical generation on the national grid was rooftop solar (and another ~10% was utility-scale solar). Rooftop solar works just fine if utilities don’t actively try and obstruct its use.

That's a great achievement, but could be stated in a more clear way.

Not 'As of lunchtime' but 'At precisely lunch time'. An hour later it wasn't 50% anymore, and it won't be 50% except at noon for a long time yet. As of the moment I am posting this, solar is 0% and coal is 80%. If Australia cares about global warming they should build nuclear plants and stop generating 70% of their overall power from coal.

It's still remarkable how much solar is growing and I hope it's 100% 24/7 soon!

Re: Satellite powered estimation of global solar potential

#189
post #116

Earlier quoted context omitted.

> incredible conversation starter for homeowners who might not have considered taking on a home solar project otherwise Once you do the math in a Northern country (sans subsidies) it's not as compelling as you might think.

Because (at least in the USA) the soft costs are excessive: https://pv-magazine-usa.com/2022/11/16/tackling-soft-costs-a...

Considering "Customer aquisition" as a cost is really funny (and that seems to be the "soft cost" discussed).

In Minnesota the "deal" for solar if you cannot DIY / off-grid is just meh.

They do not allow use of battery backups or cutover, they cut out when the power goes out, and they "credit" you to reduce your overall bill. You can make money if you produce more power in sunny warm times than you use year around (at least while you are the only one!), but the dream of energy independence at a local scale just isn't there yet.

What I want is something that offsets my grid use (potentially to zero but not negative), so that I can use grid or solar to charge my EV and a whole-home battery bank with three days reserve. I don't care about becoming part of the overall grid solution, but in city limits, it appears I must, and that necessitates extra equipment and rules out my backup use case.

And yet, I get constant calls and fliers about it - all "soft costs" - no matter how much I say no.

Re: Satellite powered estimation of global solar potential

#190
post #136

Earlier quoted context omitted.

Ahh, ok the tool sucks it doesn’t seem to calculate based on your current cost per kWh or the local cost per kWh. It’s ignoring inflation on those calculations, acting like your electric bill will be the same in 20 years. It’s also ignoring residual value in the system after 20 years they typically last 25-30, and you don’t pay taxes on savings. There install estimates where also really high for my area, but I don’t…

Your electric bill 20 years from now is just as likely to go down as it is to go up. In two decades, we could see advancements like mobile generators offering free power, ultra-affordable battery packs delivered to homes to meet energy needs, or even the widespread adoption of low-cost fusion energy. The key takeaway is that predicting the future cost of electricity is as challenging as it was to predict today’s sola…

Now you're sounding all pie in the sky. The cold hard reality is that hedge funds and billionaires control most power utilities and lobby governments to keep the cash flowing.

We know for certain that pricing is going to get really bad in CA due to a 2022 law that permits PG&E and other utilities to charge large connection fees based on your income (will probably hit in 2026).

I would gladly be the counterparty to any wager that 20 years from now electricity is going to be cheaper.

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