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Building my own solar power system

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Re: Building my own solar power system

#301

Post by vondur »

thegrim33 wrote: post #218

It's kind of telling/ironic that the author gripes (whether rightfully or wrongly) about PG&E wanting more return on investment due to their risk of doing business in California, but when the author decides to build their own power system to not deal with PG&E, literally almost every paragraph related to their planning/setup contains a mention of some different California/city regulation that the author had to meet o…

I was reading something the other day about an interesting dichotomy in California. It’s one of the most heavily regulated states, yet also one of the most lawless at the same time.

Re: Building my own solar power system

#302

Post by epistasis »

looofooo0 wrote: post #35
sneak wrote: post #27

Earlier quoted context omitted.

How many office parking lots would be covered in solar carports immediately if the corrupt PUC paid reasonable rates for generation? This solves the T&D problem too, as generation remains distributed. It’s the money.

Not so easy to reduce the grid load all the time, needs a big battery for every night and for multiple dark days you still need the grid a lot.

Big batteries are actually very easy, and getting cheap enough that they account for a significant chunk of new grid assets when there are enough renewables.

Take the Texas ERCOT market, which is the closest thing to a free electricity market that exists in the US. A huge chunk of new grid assets are batteries, becuase they are one of the most profitable things to install right now (see the map at the bottom of the page)

https://www.eia.gov/todayinenergy/detail.php?id=64586

Additionally, many people are now buying EVs, and an EV stores 2-5 days worth of electricity. If big batteries on wheels are commonplace, then simpler and cheaper immobile batteries are pretty easy too.

Re: Building my own solar power system

#303

Post by kragen »

alex-moon wrote: post #244
lazide wrote: post #149

Earlier quoted context omitted.

The issue is the payback is not worth the hate from your neighbors and capital cost. at least solar panels are quiet.

Hence "community energy" - you do it with your neighbours - this model has worked in Scotland before - https://www.resilience.org/stories/2019-07-16/rebel-cities-t... - here is one from earlier this year - https://www.thenational.scot/news/24993445.local-groups-bid-... - and recent changes in planning legislation mean we should be seeing more of these in England in the near future - https://communityenergyengland.org…

Community energy makes sense for 2,000,000-watt windmills like the ones in your first article, but not for a 600-watt rooftop windmill that's less than a meter across. The 2,000,000-watt windmill ought to cost less per watt, but it requires successfully coordinating the community to support it (cf. the note in your third link about a "de facto ban on new onshore wind projects" being lifted). And looking at https://www.canarymedia.com/articles/wind/chart-wind-turbine... it looks like over the period 02015 to 02022 the prices of big windmills consistently stayed in the range of 80¢ to 130¢ per peak watt, which is actually more than the 50¢ per peak watt of the mail-order Amazon rooftop windmill. (The rooftop windmill will probably enjoy significantly lower capacity factors, but it's clearly in the same ballpark.)

This was surprising to me, since I thought big windmills were much cheaper per watt, so I dug a bit further. The figures check out. The current https://www.bbc.com/news/articles/c80kv5d7lp7o says a £40 million (US$52 million) onshore Manx wind farm might have "up to 5 turbines", and thus up to 10 megawatts, putting the total project cost closer to US$5/Wp. https://www.eia.gov/analysis/studies/powerplants/capitalcost... from 02019 has a capital cost breakdown of a 200MW hypothetical wind project costing US$253 million, consisting of 71 2.8-MW windmills, totaling US$1265/kW (127¢/Wp). About 60% of that (80¢/Wp) is "WTG [windmill] procurement and supply". A 50MW hypothetical wind project in the next section comes in at 168¢/Wp, and a 400MW hypothetical offshore wind project in the next section is 438¢/Wp.

So it's not at all clear to me that community wind energy, or utility-scale wind energy in general, is even cheaper or more efficient than mail-order rooftop windmills. It might be more expensive!

Re: Building my own solar power system

#304

Post by bsder »

somanyphotons wrote: post #247
Havoc wrote: post #231

Suspect it would have been cheaper to invest money in upgrading the homelab and aircon to more efficient. Not downgrade, but rather moving to newer lith nodes etc. Tackling the usage before bigger battery system often makes sense

The solar system will pay for itself within N years, and then he has free power for as long as the batteries and panels last

It's really unlikely that most people will gain a lot of money from these kinds of installations nowadays (an EV probably tips that somewhat).

The big benefit is the resilience. Since you are using them every day, they will be far more likely to work in the event of an outage than a gasoline generator that you test once a year.

Re: Building my own solar power system

#306

Post by kragen »

teamonkey wrote: post #215
kragen wrote: post #138

Earlier quoted context omitted.

The swept area of the blades scales quadratically with the blade length, not exponentially. Exponential scaling is f ( x ) = knˣ , not f ( x ) = kxⁿ . The difference between quadratic scaling and exponential scaling is earth-shatteringly enormous; this is not some minor detail. With quadratic scaling, if f(1) = 1 and f(2) = 4, then f(10) = 100. With exponential scaling, if f(1) = 1 and f(2) = 4, then f(10) = 262144,…

Unfortunately I can no longer edit the post, but of course you’re right. Max generated power is proportional to (blade length)^2, therefore quadratic, not exponential.

I assumed that meant that big windmills would be much cheaper per watt than small ones, but according to what I'm finding in https://news.ycombinator.com/item?id=44056971, that doesn't seem to be the case. Small rooftop windmills may actually be cheaper!

Re: Building my own solar power system

#307

Post by metalman »

_whiteCaps_ wrote: post #180
metalman wrote: post #95

Earlier quoted context omitted.

Midnight Solar are the OG company in off grid and they have a "waste not" feature from way back that triggers any device when the parameters you set are reached, ie: float voltage, and/or other things, like a second set point where power would be sent to a third load, like the grid or water heating. https://www.midnitesolar.com/ hard core techies, even had the pleasure of detailing my inadvertant and unsucessfull att…

Midnite Classics are great... But the web APIs seem to be deprecated. Do you know of any tools that can get data off them?

nothing other than what is published in the manuals, there is a link to a third party software for monitoring the clasics, but if you want the inside story, call them....they answer the phone and speak many dialects of techinese there latest offering is a game changer "the 1" it does everything 11kw of 600 volt solar in, to any kind of 48 volt battery, and grid tie, and single,split phase and 3 phase 208 volt ac out, one box 98 lbs, 5k list you can install 200 % extra solar for low light, or norther locations specs are wild https://www.midnitesolar.com/productPhoto.php?product_ID=766...

Re: Building my own solar power system

#308

Post by dgacmu »

bruce511 wrote: post #285
aftbit wrote: post #225

Earlier quoted context omitted.

Fission first! Let's build more nuclear power plants too. We know how to do it, and it's only so expensive because we got scared and stopped. Economies of scale for clean, safe, reliable baseload power.

Turns out, I'm already on fission. What I've done is tap into an existing fission reactor. It's some distance from my house, but there's a lot of excess energy there leaking out. I put up some collectors to capture it. Was really quite cheap to do, and I don't have to pay anyone to actually run the reactor.

It's mostly a fusion reactor, to be pedantic.

Re: Building my own solar power system

#309

Post by hansvm »

singleshot_ wrote: post #295
gosub100 wrote: post #255

Earlier quoted context omitted.

> hydroelectric, so already green Not so fast. Zero emissions, yeah. But they have damaged the habitat for some bird species.

Would love to see your analysis of Thanksgiving

You mean the turkey voluntary extinction movement?

Re: Building my own solar power system

#310

Post by bruce511 »

dgacmu wrote: post #308
bruce511 wrote: post #285

Earlier quoted context omitted.

Turns out, I'm already on fission. What I've done is tap into an existing fission reactor. It's some distance from my house, but there's a lot of excess energy there leaking out. I put up some collectors to capture it. Was really quite cheap to do, and I don't have to pay anyone to actually run the reactor.

It's mostly a fusion reactor, to be pedantic.

rats... I meant fusion :) There's me getting my nuclears all mixed up...
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