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Puerto Rico's Solar Microgrids Beat Blackout

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191–200 of 251 posts

Re: Puerto Rico's Solar Microgrids Beat Blackout

#191

Earlier quoted context omitted.

5kWh of batteries is under $1000. That's enough for load shifting for most people. Even if you need several of them, that's still going to be cheaper than installation labor.

where are you buying 5 kWH of batteries for under $ 1,000? The typical 5 kWh battery in Canada is C$ 3,000 - 4,000.

https://signaturesolar.com/all-products/batteries/?_bc_fsnf=...

Server rack style, 1200 USD for 4.8 kWh = $250/kWh. Wall-mount, 14.3 kWh for $3.3k = $231/kWh.

These guys seem to be the biggest DIY solar equipment supplier in the US.

Afaik you can get batteries from China (AliExpress) for quite a bit cheaper too.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#192

Earlier quoted context omitted.

California announced they were going to do the same.

Yeah the channelized sections of the Colorado would be a good candidate as well, though I personally believe the bigger solution is reintroducing beavers into the upper water shed, to increase total average flow.

How do beavers increase total water flow? I can see them causing more water to be held upstream.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#193
post #154

Earlier quoted context omitted.

Michigan unfortunately represents a mismatch of when you need power vs when power is generated. Arizona, Texas, New Mexico are sweet spots. High power demand in the summer (A/C), relatively high proportion of sunny days.

Michigan is just like the south: highest electricity consumption is during summer. This may change with increased use of heat pumps for heating, but it’s still a while out before seasonal electricity consumption patterns invert. +/- on what effect electric cars will have: people drive more in summer but efficiency goes down in winter. Arizona, Florida, etc are not really in a sweet spot we all think it is because PV…

Interesting that PV efficiency is impacted by peak heat. Why are there so many solar farms in the desert near Las Vegas and in West Texas then? Serious question, would love to know the answer. Are these inefficiencies just now coming to light?

Re: Puerto Rico's Solar Microgrids Beat Blackout

#194
post #193

Earlier quoted context omitted.

Michigan is just like the south: highest electricity consumption is during summer. This may change with increased use of heat pumps for heating, but it’s still a while out before seasonal electricity consumption patterns invert. +/- on what effect electric cars will have: people drive more in summer but efficiency goes down in winter. Arizona, Florida, etc are not really in a sweet spot we all think it is because PV…

Interesting that PV efficiency is impacted by peak heat. Why are there so many solar farms in the desert near Las Vegas and in West Texas then? Serious question, would love to know the answer. Are these inefficiencies just now coming to light?

The effect has long been known, but it's pretty modest. Here's the data sheet for a typical modern solar panel:

https://static.trinasolar.com/sites/default/files/Datasheet_...

It loses about 0.29% of (relative) power output for every degree Celsius of temperature increase. If the module is operating at its maximum rated temperature of 85 degrees C, it's still about 83% as efficient as it would be under standard test conditions (25 degrees C).

Solar farms in sunny, hot regions generate more energy per year than identical installations in cooler, less sunny regions. The benefit of extra light dominates over the efficiency loss from higher temperatures. A location with as much sunlight as Las Vegas but the temperatures of Anchorage would be ideal, but there are few if any locations with those characteristics. That's why Las Vegas is still a good location for solar farms despite the heat.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#195
post #55

Earlier quoted context omitted.

That's the case everywhere in the world, it's not a tech issue. The tech exists.

It’s a corruption issue where certain people use it as a personal bank. Lots of deferred maintenance, no build out, but lots of greed -not just a little.

The political system there clearly allows for high levels of corruption.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#196
post #53
post #51

Earlier quoted context omitted.

It's not just redistribution, land is an already heavily overcommitted resource on Earth. China, for example, holds basically same amount of land as US, for its 4x population, and they house the people in things like dozens per each clusters of 50-story condominiums. In places like that - that but not necessarily specifically China or Asia, local proprietors would head to forested mountains unfit for residences, and…

"local proprietors would head to forested mountains unfit for residences, and actively desertify it to put on PVs to collect incentives, if incentivized." Can you give me one example, where PVs contributed to desertification? Usually it is the contrary, in the shade of the PVs, more can grow than in direct burning sunlight. And there are plenty of non forest land, or literal dessert land tp put PV there and if forest…

https://coloradomtn.edu/news/cmc-news/new-solar-array-and-ba...

https://www.swissinfo.ch/eng/sci-tech/mountaintop-solar-farm...

www.gettyimages.co.uk/detail/photo/birds-eye-view-of-the-solar-power-plant-and-lush-royalty-free-image/1338844539

www.gettyimages.co.uk/detail/photo/aerial-view-of-solar-power-station-royalty-free-image/1045649830

https://www.ecoportal.net/en/carpeting-mountains-with-solar-...

Just go look at it if you were looking for shocking images. Notice how suspiciously flat patches appear in the mountains just for the PVs and notice how panels often seem recessed below top of existing trees. The process of solar farm construction in such areas begins by clearing out existing life. That's how it's done. It doesn't go like, you just pick a dead land on map and giving out a free nice shed for local scorpions.

I mean, look at even East Coast of the US on Google Maps. Pick any areas just off a city and zoom in. There would be towns, farmlands, forests, mountains, or combinations thereof. If you do the same in the West Coast, you are more likely to hit such suitable flats that can host mega electricity farms and benefit from it, sure, but that's not even universally American thing.

Then you'd ask, can't those deserts like Gobi or Sahara or whatever provide enough land for PVs and PVs be good for those? Maybe, but that's terraforming scale of projects. Not microgrids.

It's not like skyscraper residential buildings exist solely because it's convenient to confine workers near factory sites or because the laborers own nothing - it starts appearing when it becomes impossible to simply distribute immediately available lands and land had become a contested resource. Think why they don't just expand cities outward or build new city cores. They don't because those buildings are solution to that becoming impossible. And with that, think again why they just go out and build those microgrids in cheap unused flat areas outside the city. Because there is no cheap unused flat areas outside the city.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#197

i live in puerto rico. I talk with my luma friends all the time, we need baseload. We need more gas. We've made huge investments in solar that have been destroyed by hurricanes and are a huge waste issue.

i got really tired of Luma and after the new year blackout i jumped ship to windmar. i'm fairly rural so it's actually decent and in a good spot where other neighbors have fared well during hurricanes.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#198
post #166

Earlier quoted context omitted.

"If you want to run your home loads, the cheapest/simplest way (without going grid-tie) is to have an electrician add a critical loads panel supplied by your inverter output ..." No, that's actually not the simplest. Far simpler is to install a solar breaker in your main panel and a physical lockout[1] between utility power and the new solar breaker. There is no ATX, there are no smarts, the power goes out and you fl…

Changing your usage pattern isn't simpler. When I mean simplest, I meant a solution that doesn't rely on doing anything. If/when Solar isn't enough or your batteries deplete, it just falls back to grid. Power outage? Your critical items automatically are backed by solar/battery. Having to think about your what high draw appliances are running and using additional power adds mental load (ie complexity) and is an immed…

Changing your usage pattern is ultimately at the heart of any serious proposal for solving energy scarcity. We have enough energy to power our civilisation without catastrophe: we're just using it in an extremely inefficient manner.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#199

Earlier quoted context omitted.

It is not necessary for the majority to install solar. Pakistan had similar problems with rolling blackouts, and mass import of photovoltaic equipment and batteries from China has reduced the load on the grid so that outages no longer occur frequently. In fact the demand has shrunk so much that it jeopardizes financing of coal power companies. https://news.ycombinator.com/item?id=43620309

> In fact the demand has shrunk so much that it jeopardizes financing of coal power companies. That is something that I think would be the impetus needed to motivate reduction in coal power plants. If they become unprofitable to operate, then will the market finally decide to stop using them? Sadly, I could see the current US administration deciding to offer subsidies to keep coal.

Yes, it is happening already (both the pivot away from unprofitable non-renewable energy, and US government intervention to tax imports of photovoltaics).

Levelized Cost of Electricity (LCE) from PV is below the fossil fuel range since 2020, and since 2024 it is also below if you include battery storage, which you need to turn solar into near constant energy supply.

https://www.irena.org/Publications/2024/Sep/Renewable-Power-...

https://electrek.co/2025/06/20/batteries-are-so-cheap-now-so...

Re: Puerto Rico's Solar Microgrids Beat Blackout

#200

I would love to have just enough solar to flatten my peak usage on the hottest days of the summer. They naturally coincide with tons of sun. I don't need a huge system to be all solar all the time or even care about credits from the power company. I just don't want a $300 bill in the summer and a $50 bill in the winter. Has anyone designed a good solution for this?

Get a direct solar AC minisplit, EG4 makes one that I haven't tried but it's around $1500 not including panels.

It won't ever make excess electricity and you won't be able to run it after dark, but it'll keep you nice and chilly, I bet.

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