Need some advice on solar gear

[MacWhinny]

Hello all,

I would like to lower the amount of juice my PC uses from the mains and have been looking at placing a solar pannel (Just 100W) outside my window. I have one of those slanted ground floor sticking out windows below my room and the slanted roof is at a 50/60 degree slant, and I get the sun from 10/11 am

I'm looking for any suggestion for a battery pack that will use solar energy first before switching over to mains power when it gets to a set power amount.

I'm currently using around 200KWH a month and even a 100w pannel would help lower it and hopefully keep the estate agents off my back

 

[Geoff1946]

If you use a laptop there are readily available cheap power supplies to run it off a 12 volt battery.
You can also get a charge controller which would connect your solar panel to maintain the battery. This is all straightforward readily available gear as I use on my caravan.

If you want to run a mains powered desk top PC I think you need an invertor, but beware, not all invertors are compatible with all loads. Either way I recommend using a leisure battery and controller, to provide a stable source.

 

[MacWhinny]

If you use a laptop there are readily available cheap power supplies to run it off a 12 volt battery.
You can also get a charge controller which would connect your solar panel to maintain the battery. This is all straightforward readily available gear as I use on my caravan.

If you want to run a mains powered desk top PC I think you need an invertor, but beware, not all invertors are compatible with all loads. Either way I recommend using a leisure battery and controller, to provide a stable source.

Hello, It's for a PC with a 4090.

I'm looking to supplement the power, i want a battery that would allow solar input to reduce the amount of power coming out of the wall, but that would switch over to mains power when 1 solar output reduces and or when the battery gets to a set power lvl while having solar power incoming to the battery would switch over to mains power to keep the battery above a set amount. If that makes sense. I'm unsure if I'm explaining it right

Any link to gear for that setup would be helpful. I'm not looking to spend too much if at all possible.

 

[Geoff1946]

I don't know what a 4090 is, but assume you want 230 volt mains.
I think you would still need to have a battery and invertor, like a UPS system and then a charge control system which recognises the two power sources, (solar or mains), gives solar priority and maintains the battery.
I don't know if or where such items exist but my gut feeling is that it will all cost more than it's going to save you.

Stay around. Someone else may have better ideas.

 

[MacWhinny]

I don't know what a 4090 is, but assume you want 230 volt mains.
I think you would still need to have a battery and invertor, like a UPS system and then a charge control system which recognises the two power sources, (solar or mains), gives solar priority and maintains the battery.
I don't know if or where such items exist but my gut feeling is that it will all cost more than it's going to save you.

Stay around. Someone else may have better ideas.

Yeah, i guess i'm looking for something that can switch between them that has options of what has priority and at what power lvl the battery starts taking mains power while still accepting solar.
I realise that solar wouldn't fill the battery as I'm on my PC from around 12pm till after sunset. But it's mostly to reduce the 200KWH I'm using.


Also a 4090 is a Nvidia GPU

 

[Geoff1946]

Just invest in a grid linked solar system.

 

[MacWhinny]

that sounds more like a system that would be tied into the grid and I rent in a shared house. So can't do any alterations to the building and such. I'm just looking for something I can hang out my window and have setup in my room

 

[Richard-the-Ninth]

Why don't you buy an energy monitor Click me You can see what is using so much energy

The idea of solar to run things is great, but for one item (as you are looking to do) it is going to cost around £1,500 for a small kit, for a remote location or boat that is acceptable, but for a house that already has an alternative...................

I really would suggest you look into what is using the most electricity in your house.

 

[binky]

that sounds more like a system that would be tied into the grid and I rent in a shared house. So can't do any alterations to the building and such. I'm just looking for something I can hang out my window and have setup in my room

Amazon has quite a few portable power packages, but I doubt they would really be much use from what you are saying. If you have any form of off peak electricity tariffs, a rechargeable battery pack might be more use.

 

[johnb2713]

Hello all,

I would like to lower the amount of juice my PC uses from the mains and have been looking at placing a solar pannel (Just 100W) outside my window. I have one of those slanted ground floor sticking out windows below my room and the slanted roof is at a 50/60 degree slant, and I get the sun from 10/11 am

Financially it's simply not worth it.

A 100w panel is at best likely to give you 80w in good conditions. If youre lucky weather wise, that may happen 50% of the time for an average of 6 hrs per day. That gives you a potential energy of around 85 kWh per year which is less than £20 cost. You may be better to look at your PC and reducing it's consumption.

 

[MacWhinny]

Why don't you buy an energy monitor Click me You can see what is using so much energy

The idea of solar to run things is great, but for one item (as you are looking to do) it is going to cost around £1,500 for a small kit, for a remote location or boat that is acceptable, but for a house that already has an alternative...................

I really would suggest you look into what is using the most electricity in your house.

I already have an energy monitor and my entertainment system uses around 200KWH a month. That includes my PC, TV, 2 mini PCs, 2 fans, speakers, router, Pi4, water cooling bed cover (I get hot at night ) My estate agents are already breathing down our necks as, as a household, we are using double our allowance in electric (We get around 373KWH a month for a 4 bed shared house)

 

[MacWhinny]

Financially it's simply not worth it.

A 100w panel is at best likely to give you 80w in good conditions. If youre lucky weather wise, that may happen 50% of the time for an average of 6 hrs per day. That gives you a potential energy of around 85 kWh per year which is less than £20 cost. You may be better to look at your PC and reducing it's consumption.

Hmmmm, I've already reduced everything to as low as I can. Turning PC off at night, turning appliances off, unplugging things I don't use often. putting my PC into energy-saving options, using a low-powered GPU for general gaming instead of my 4090 (I have a high-end PC) But still, use around 200KWH a month. I was looking into another way of reducing the overall energy usage.

 

[jameslaurieuk]

You could start off by looking at a UPS, this gives you the ability to switch between battery and mains without interrupting the PC. You can pick them up cheap from eBay and replace / expand the battery packs in them quite easily.

Next is to decide how to charge it, on the mains side you could go panel to controller to inverter to UPS or you could get dirty with the internals and go direct from panel to controller to batteries with a 12v connection.

But then how do you switch back to mains when the batteries get depleted? The UPS will give audio and visual warnings that it’s batteries are getting low so perhaps you could hook into that circuit to throw a relay on the 240v input to switch from inverter (or nothing) to mains?

Sounds like a fun project but not sure it’s going to be cost effective!

 

[MacWhinny]

You could start off by looking at a UPS, this gives you the ability to switch between battery and mains without interrupting the PC. You can pick them up cheap from eBay and replace / expand the battery packs in them quite easily.

Next is to decide how to charge it, on the mains side you could go panel to controller to inverter to UPS or you could get dirty with the internals and go direct from panel to controller to batteries with a 12v connection.

But then how do you switch back to mains when the batteries get depleted? The UPS will give audio and visual warnings that it’s batteries are getting low so perhaps you could hook into that circuit to throw a relay on the 240v input to switch from inverter (or nothing) to mains?

Sounds like a fun project but not sure it’s going to be cost effective!

I already have a UPS (EATON ECO 1600) setup for my mini PCs, so I guess it's just the inverter and panel then. I'd need an inverter that can pull both solar and mains at the same time that has options to keep the mains power at say 80% charge but keep solar charging when it can. Or something that will not drain the battery but not keep it full while there's solar energy coming in. The cheap stuff doesn't have any features like that from what I've seen

 

[Richard-the-Ninth]

How do you know it is YOU/your stuff that is using 200KWH a month (A breakdown would help) after all you did say you are in 4 bed shared house.
How do you all cook?

 

[johnb2713]

Hmmmm, I've already reduced everything to as low as I can. Turning PC off at night, turning appliances off, unplugging things I don't use often. putting my PC into energy-saving options, using a low-powered GPU for general gaming instead of my 4090 (I have a high-end PC) But still, use around 200KWH a month. I was looking into another way of reducing the overall energy usage.

Take a good look at the power supply you have, there are some amazing differences in efficiency.

 

[binky]

I already have a UPS (EATON ECO 1600) setup for my mini PCs, so I guess it's just the inverter and panel then. I'd need an inverter that can pull both solar and mains at the same time that has options to keep the mains power at say 80% charge but keep solar charging when it can. Or something that will not drain the battery but not keep it full while there's solar energy coming in. The cheap stuff doesn't have any features like that from what I've seen

what you need is a battery pack that can be charged from solar or mains, charge up using solar for as long as possible before switching to mains - you may have to manually switch over from solar to mains powwer for your devices, but if you are using a laptop, they have a battery so will keep you working whilst doing that. Trouble is anything any good comes at a price. link below is the sort of thing I'm thinking about https://www.amazon.co.uk/VTOMAN-Por...b6e3d217f&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1

 

[MacWhinny]

How do you know it is YOU/your stuff that is using 200KWH a month (A breakdown would help) after all you did say you are in 4 bed shared house.

As you can see below, this is my energy usage for the last 33days. One to look at is mains 1 for the total per month. The Main PC uses the most and is just my PC usage.

Ignore mains 2. I have energy monitors on all of my sockets that i want to track.

 

[MacWhinny]

Take a good look at the power supply you have, there are some amazing differences in efficiency.

Do you mean PSU or electric providers?

 

[johnb2713]

Do you mean PSU or electric providers?

The Switch Mode Power Supply inside your PC. We ran several Bitcoin mining systems (small farm), we used around £5,500 per month in electricity. Researching the power supplies we reduced the heat output, the electricity consumption, the bills dropped to around £4400 per month just by swapping PSU's, there was no loss of performance.