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Puerto Rico's Solar Microgrids Beat Blackout

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Re: Puerto Rico's Solar Microgrids Beat Blackout

#231

Post by naasking »

supplied_demand wrote: post #230
naasking wrote: post #122

Earlier quoted context omitted.

> Is there a part of the US’s 250 year history where we weren’t bringing in immigrants from poorer countries to provide cheap labor? Pretty sure they're referring to a de facto open border policy, where you basically permit all sorts of illegal immigration and don't really enforce the laws. Accepting immigrants at Ellis island was not illegal immigration, for instance, but crossings at the southern border often have…

== Pretty sure they're referring to a de facto open border policy,== I’m summary, not open borders. There have been about 20k border patrol agents in the US each year since 2008. Seems like a lot of agents for an open border policy. https://www.azcentral.com/story/news/politics/border-issues/...

De facto policies are still active policies, even if they aren't de jure.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#232

Post by lukan »

numpad0 wrote: post #196
lukan wrote: post #53

Earlier quoted context omitted.

"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 a…

Ok, I checked the one link about swiss where I have local info .. and can you please show me the shocking image?

I am not a fan of building much on top of the mountains in general, but the claim was about desertification and at least that link provided nothing about it. Are the others more worth it?

The gettypictures just show solar panels on what was grasland before.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#233

Post by hinkley »

sand500 wrote: post #192
hinkley wrote: post #189

Earlier quoted context omitted.

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.

Forests make rain, and beavers make better forests.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#234

Post by rtkwe »

Symbiote wrote: post #179
thmsths wrote: post #112

Earlier quoted context omitted.

I feel the real danger of back feeding is not that american line workers can't be bothered to check if the line is truly dead before starting to work. It's that the line could be reenergized at any time.

Lineworkers will ground/earth the line with a very good connection (e.g. metal rod into the ground) before working on it, as far as I know. (At least, this is what electricians working with 33kV in industry in Europe do, e.g. if doing maintenance on a cable to a datacentre.)

I haven't seen them doing that on power outage post storm line repairs near me, usually during those they're working as fast as possible because they have dozens of other spots they need to repair.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#235

Post by rtkwe »

derbaum wrote: post #222
nandomrumber wrote: post #217

Earlier quoted context omitted.

You’d be surprised how few watts a fridge and a TV draw, 500 watts combined, and that’s only while the compressor in the fridge is running. Don’t open the fridge very often, or keep a lot of thermal mass in the form of filled water bottles in there, and the compressor in a fridge will spend most its time not running.

Now I'm curious... Is your last suggestion correct? Wouldn't the time to cool down between pause intervals be proportionally longer due to the higher thermal mass and cancel out any savings gained by the long pause? Maybe the overall energy draw is even higher because the heat losses are higher when you spend a longer time with a high dT.

The water bottles don't warm up as quick as the air they replace that flows out of the fridge when you open it; so they have two effects first they take up space that new hot indoor air can't move into and second they then help chill that air slightly through their own thermal mass.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#236

Post by eldaisfish »

bob1029 wrote: post #227
briHass wrote: post #216

Earlier quoted context omitted.

The bang-on, bang-off compressors are a dying breed, however. The efficiency and output modulation of the inverter units means even the conventional split systems have been switching over. Likewise, the 'minisplit' (originator of these efficient compressors) definition has expanded to include ducted models, even ducted models with conventional high-cfm blower wheels.

Putting semiconductors in front of a 3+ ton heat pump when you live in a rural area is guaranteed bad times. Not only can you not find many people who have parts or knowledge on hand, but you also have to deal with the fragility of the system. A single stage compressor is very robust to electrical transients. These units can take direct lightning strikes and continue to function normally. Worst case, you replace a co…

the factors that kill semiconductor switches are heat and voltage switching transients. This is why the 800 V electronic components in some EVs fail - the voltage.

The voltage in a heat pump is 240 V. The power is typically a couple of kilowatts. Reliability of silicon switches at that voltage is excellent. This is just not a widespread problem.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#237

Post by BenjiWiebe »

rtkwe wrote: post #234
Symbiote wrote: post #179

Earlier quoted context omitted.

Lineworkers will ground/earth the line with a very good connection (e.g. metal rod into the ground) before working on it, as far as I know. (At least, this is what electricians working with 33kV in industry in Europe do, e.g. if doing maintenance on a cable to a datacentre.)

I haven't seen them doing that on power outage post storm line repairs near me, usually during those they're working as fast as possible because they have dozens of other spots they need to repair.

Hopefully they're bonding the line to their bucket at least.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#238

Post by sheepybloke »

dylan604 wrote: post #178
chithanh wrote: post #34

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.

This has been happening in the US for the past 10 years. The big switch has been away from coal and some slower natural gas generators towards more nimble natural gas generators. Coal and other natural gas generators take a while to start up and shut down (think on the order of a day), which don't work well for coordinating with renewables and are much more expensive to operate. So companies have been switching to faster natural gas generators that start up in minutes to hours to support when demand is higher.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#239

Post by supplied_demand »

naasking wrote: post #231
supplied_demand wrote: post #230

Earlier quoted context omitted.

== Pretty sure they're referring to a de facto open border policy,== I’m summary, not open borders. There have been about 20k border patrol agents in the US each year since 2008. Seems like a lot of agents for an open border policy. https://www.azcentral.com/story/news/politics/border-issues/...

De facto policies are still active policies, even if they aren't de jure.

You haven't demonstrated that it is de facto policy, only asserted that it is.

Re: Puerto Rico's Solar Microgrids Beat Blackout

#240

Post by supplied_demand »

miningape wrote: post #84
supplied_demand wrote: post #73

Earlier quoted context omitted.

== Currently, in western countries, socialist policies to import the 3rd world and open borders are directly responsible for the lowering social trust.== I don’t know of any western country with an “open borders” policy, can you provide one? Is there a part of the US’s 250 year history where we weren’t bringing in immigrants from poorer countries to provide cheap labor?

For very specific examples you can look towards the EU's decades long stance on immigration which resulted in the refugee crisis since (and before) 2015, as well as countless integration and immigration issues (cf Sweden, France, Italy, etc.). The socialist and left wing coalition have consistently voted against measures to improve border security and tighten the restrictions for people wanting to enter [1]. As peopl…

==We can also look towards the UK where socialist politics have been a mainstay since the 90s,==

The UK was lead by the Conservative party continuously from 2010-2024. You somehow skipped all of that and went straight from Tony Blair to Keir Starmer.

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