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Building my own solar power system

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Re: Building my own solar power system

#131

Post by 7952 »

pjc50 wrote: post #80
alex-moon wrote: post #10

Having done some work around net zero policy I am increasingly convinced that this is the way forward, and indeed that this will be the way things are done normally maybe 10-20 years from now. The concept is called "distributed generation" and in UK each distribution network keeps an "embedded capacity register" which is basically all the distributed energy resources that are connected to the grid at distribution lev…

One of those areas where policy action is desperately needed but no attention is paid due to media dysfunction. I think the UK would benefit from region-specific pricing, to move the datacenters closer to generation rather than urban environments. It would also encourage more embedded generation in expensive areas.

The cost for generators to connect is already based on region (TNUoS pricing).

Re: Building my own solar power system

#132

Post by bmqpo »

With power issues in Nigeria (basically no power from my perspective), I have been building my home solar system. Currently at 9kw solar panels, 10kva inverter with 30kwh Chinese LFP. Spent about $7,000 so far. Looking to eventually get to 60kwh and at least 20kw in panels because of air conditioning needs.

Waiting for government, my kids currently in primary school would probably have graduated from college before they fix the power situation (they are currently fixated on building roads to nowhere).

Re: Building my own solar power system

#133

Post by philjohn »

KaiserPro wrote: post #90

I have a solar system in my house in london. 5kw, 13kwhr battery. I am self sufficient from end of march to october. I recently got a second hand electric car. I bought an EV plug (total fucking ripoff. its a fucking plug with a contactor, RCD and a CAN interface. no way is that worth fucking £600) It has some basic control to allow me to charge from excess solar. What is not easy to do is charge at night without dra…

I mean, it's a bit more than a contactor and an RCD, it also has PEN fault detection because TN-C-S is how most of us are wired up to the grid.

Then for use with smart tariffs like IOG there's a microcontroller, cloud gateway for them to hook into for OCCP to turn on and off the charger when the grid is cheapest/greenest etc.

So £600 is about right, once you add in R&D, certification, profit margin, warranty claim % etc.

Re: Building my own solar power system

#134

Post by kragen »

cyri wrote: post #63

I did build my own solar system too. In Switzerland. Took me 1-2 month planning and then 3 month building it alone nearly each day. Sept 2023 til Xmas 2023. Got all the hardware from a PV dealer friend on his purchase price level. Even 24 panels I have put myself alone onto the roof. With two persons it was a bit better. I've got: 420w x 71 Trina solar panels and two SolarEdge inverters. SE10K Hybrid and a SE17k. Als…

How much did you pay for the panels, and what's your capacity factor? (Kilowatt hours produced on average per nominal peak kilowatt.)

Re: Building my own solar power system

#135

Post by kragen »

looofooo0 wrote: post #18
alex-moon wrote: post #10

Having done some work around net zero policy I am increasingly convinced that this is the way forward, and indeed that this will be the way things are done normally maybe 10-20 years from now. The concept is called "distributed generation" and in UK each distribution network keeps an "embedded capacity register" which is basically all the distributed energy resources that are connected to the grid at distribution lev…

Well problem in the UK is that in summer there is like a magnitude more power from PV then in winter.

No, having more power isn't a problem for solar; unlike coal or nuclear, solar can curtail production instantly and without suffering wear and tear. The problem is that in the UK in the winter there is an order of magnitude less power from PV than in the summer.

Re: Building my own solar power system

#136

Post by eldaisfish »

Teever wrote: post #52
calgoo wrote: post #47

Earlier quoted context omitted.

I personally feel there should be more allowance for small personal wind generators in sub-urban areas. That would offset a bit at least in winter for places like the UK. Not sure what the actual laws are, but I can assume councils wont be too happy about someone putting one up on their home.

I was under the impression that small wind generators at the scale of suburban backyards are really uneconomical and don't produce sufficient energy for anything of practical use.

small wind turbines are also horrendously unreliable because of mechanical failure. Same logic as to why pickup trucks are generally more reliable than a smart car.

Re: Building my own solar power system

#137

Post by kragen »

detaro wrote: post #53
calgoo wrote: post #47

Earlier quoted context omitted.

I personally feel there should be more allowance for small personal wind generators in sub-urban areas. That would offset a bit at least in winter for places like the UK. Not sure what the actual laws are, but I can assume councils wont be too happy about someone putting one up on their home.

Wind generators really scale with size though. Small ones rarely make sense

If the objective is to reduce the number of hours you're not self-sufficient for a given battery size, or reduce the size of your expensive batteries, even a couple hundred watts could make sense.

https://www.amazon.com/NINILADY-Vertical-Generator-Controlle... is a 600-watt-peak wind generator, designed for 11m/s winds, for sale in the US for US$300, presumably much cheaper in countries that aren't descending into kleptocratic tyranny. (I talked to someone who recently bought something similar for US$60. I think it was a 300-watt turbine.) It's a vertical-axis type, less than a meter in diameter. No worries about annoying the neighbors, and it'll probably do a great job of keeping your fridge running most of the time when it's cloudy.

50¢ per peak watt would be a terrible, uncompetitive price if you were a utility company considering how to build a wind farm to sell power for profit. But, if you're a homeowner seeking energy self-sufficiency because your Public Utilities Commission is trying to throw you under the bus because of regulatory capture, it's pretty affordable.

Re: Building my own solar power system

#138

Post by kragen »

teamonkey wrote: post #115
b112 wrote: post #101

Earlier quoted context omitted.

I wonder what studies may exist on this. Were they all funded by Big Wind?

Laws of physics: maximum power that can be generated is proportional to the swept area of the blades. So it scales exponentially as blade length increases.

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, a 2600× difference. And the difference gets bigger from there on out.

Re: Building my own solar power system

#139

Post by bencyoung »

KaiserPro wrote: post #90

I have a solar system in my house in london. 5kw, 13kwhr battery. I am self sufficient from end of march to october. I recently got a second hand electric car. I bought an EV plug (total fucking ripoff. its a fucking plug with a contactor, RCD and a CAN interface. no way is that worth fucking £600) It has some basic control to allow me to charge from excess solar. What is not easy to do is charge at night without dra…

We have https://www.myenergi.com/ for our car charger and it seems to be able to integrate batteries, charging and panels like you suggest, only you have to go all in. We have parts of it and are tempted to use more, but the lock-in angle is a bit off-putting

Re: Building my own solar power system

#140

Post by kalleboo »

jmb99 wrote: post #15
9dev wrote: post #4

I'm still curious what you'd need a rack consuming 1kw for… in your garage. From the photo, it looks like lots of storage(?).

My hard drives alone pull 200W idle and I don’t have that many. Cooling fans (in servers) pull 150W total most of the time but can be up to 300W. Each 10GbE NIC pulls ~40W. PoE switch gives ~30W to each of my APs, and uses ~80W itself, so there’s another 300W. All of my RAM pulls about 250W (admittedly there’s nearly 2TB of it in the rack, but still). Start adding up CPUs idle/average/max power and the numbers get wa…

40W for a 10GbE NIC sounds crazy, my internet router has a dual 10 GbE Intel NIC with one 10GBaseT SFP+ and one 10G DAC and the whole router only draws 24 W (Lenovo ThinkCentre Tiny)

My whole “rack” draws about 120W total with: aforementioned router, Synology NAS with 4 drives, 2x10G+4x2.5G PoE switch powering a Ubiquiti AP, 16-port 1G switch, and a PowerBook 540c running AppleTalk routing

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