Any electricians on here? Question about wiring my house to run on batteries.....

Makhaira · 28 Jun 2012 at 22:19

You really need to get exact numbers to be able to run this, but my suspicion would be that there is going to be a significant installation cost which might well render this cash neutral or negative - I'd get this checked out before spending more time on the endeavour.

If you're looking at options to use an initial outlay to provide longer term savings, have you considered looking at a ground source heat pump for your heating needs?

snedie · 28 Jun 2012 at 22:30

Makhaira said:
You really need to get exact numbers to be able to run this, but my suspicion would be that there is going to be a significant installation cost which might well render this cash neutral or negative - I'd get this checked out before spending more time on the endeavour.

If you're looking at options to use an initial outlay to provide longer term savings, have you considered looking at a ground source heat pump for your heating needs?

Unfortunately we only have a 25ft garden, barely enough to get any useful amounts of heat, and due to neighbouring houses getting a boring machine in isn't feasible.

norm · 28 Jun 2012 at 22:34

gumpy321 said:

This coming from the same guy who set fire to his dishwasher in his back garden.

snedie · 28 Jun 2012 at 22:44

norm said:
This coming from the same guy who set fire to his dishwasher in his back garden.

And melts spanners

....still waiting on him trying to pop that 5000amp fuse.

Fourstar · 28 Jun 2012 at 23:30

Some other posters have mentioned efficiency and I will again.

You are taking 240V ac, stepping down the voltage, rectifying, charging a battery, discharging a battery, passing through an inverter to return to 240V ac. Every one if those steps loses power.

Another thing to bear in mind is power factor. Anything other than a purely resistive load (like an incandescent light bulb) has a pf below 1. This means for a given energy usage it actually draws more than you'd expect (the details escape me so you'll have to look it up). For domestic users the power company foots the bill but as you're decoupled you may have this to deal with as another inefficiency.

I don't know what the end to end loses are but they will take a significant chunk out of your savings and hence you return on investment.

I'd love to see the figures if you collate them. Unfortunately I suspect your proposed scheme isn't economic for the simple reason it is not already in widespread use.

Blue160 · 28 Jun 2012 at 23:31

snedie said:
Also not to brag "Liampope" but I'm spending close to £5k on a new rig, plus the £2.5k I need for rent leaves me with around £3.5k left from my years wages (The bulk of which I earn in the next 6 months).

I don't get this bit. You take home 10k, spend half of that on a PC, and another 2.5k on rent. You're planning on spending the rest on batteries in the hope of saving money a few years down the line?

Am I missing something or does that leave you no money for food, clothes, transport, council tax, utility bills, or any other of the things you need to live?

Antelopethy · 29 Jun 2012 at 00:21

I still don't understand how you can use £200 a month in electricity - I live in a house of 6, 4 of us being computer scientists with high powered gaming PCs, TVs, large speaker systems etc. and our last quarterly bill was ~£300 for electricity and gas! How many people do you live with?

snedie · 29 Jun 2012 at 07:35

Blue160 said:
I don't get this bit. You take home 10k, spend half of that on a PC, and another 2.5k on rent. You're planning on spending the rest on batteries in the hope of saving money a few years down the line?

Am I missing something or does that leave you no money for food, clothes, transport, council tax, utility bills, or any other of the things you need to live?

£2.5k is all I need to "live" for a full year. This is rising monthly however, by the end of the year it will be around £3k.

snedie · 29 Jun 2012 at 07:41

Antelopethy said:
I still don't understand how you can use £200 a month in electricity - I live in a house of 6, 4 of us being computer scientists with high powered gaming PCs, TVs, large speaker systems etc. and our last quarterly bill was ~£300 for electricity and gas! How many people do you live with?

It has a lot to do with washing clothes and bedding, both me and my father suffer with severe eczema and the days clothes and bedding is washed every day along with towels. We also use an immersion heater at times to increase water temp to a level which kills bacteria, this alone attributes to £45~/pm.

snedie · 29 Jun 2012 at 07:48

Fourstar said:
Some other posters have mentioned efficiency and I will again.

You are taking 240V ac, stepping down the voltage, rectifying, charging a battery, discharging a battery, passing through an inverter to return to 240V ac. Every one if those steps loses power.

Another thing to bear in mind is power factor. Anything other than a purely resistive load (like an incandescent light bulb) has a pf below 1. This means for a given energy usage it actually draws more than you'd expect (the details escape me so you'll have to look it up). For domestic users the power company foots the bill but as you're decoupled you may have this to deal with as another inefficiency.

I don't know what the end to end loses are but they will take a significant chunk out of your savings and hence you return on investment.

I'd love to see the figures if you collate them. Unfortunately I suspect your proposed scheme isn't economic for the simple reason it is not already in widespread use.

Absolutely correct there are a lot I places to loose energy. I won't be doing this until next year, I need quotes from all the suppliers to get the best prices as well as sourcing all the kit there after. If the numbers don't support a return within 3 years this isn't going to happen.

I'll post up any of my findings either way, it will prove interesting at the least.

Blue160 · 29 Jun 2012 at 08:02

snedie said:
£2.5k is all I need to "live" for a full year. This is rising monthly however, by the end of the year it will be around £3k.

But by your figures your leccy bill is about £2.4k alone (12x200) which leaves you £100 for the year to live on :confused:

snedie · 29 Jun 2012 at 12:18

Blue160 said:
But by your figures your leccy bill is about £2.4k alone (12x200) which leaves you £100 for the year to live on

I don't foot the entire bill, only £75 each month. The rest covers food & washing, anything else I have to pay out my own pocket. I normally save around £1k a year for anything else I need.

Danny UK · 29 Jun 2012 at 13:18

Hi Snedie,

You wouldn't be able to use a make before break switch to switch between the mains and the battery supply as they wouldn't be electrically synchronised. You'd have to actually break the supply to the load or get something called a static switch which would sync the supplies to avoid dropping the load.

A couple of other things I've come across with battery systems before is be careful as to when the Ah figure is given for, I.e at day one or at the end of their useful life. Secondly it's worth bearing in mind that at the end of the batteries life they'll have to be disposed of, which will I would have thought be chargeable.

snedie · 29 Jun 2012 at 18:03

Danny UK said:
Hi Snedie,

You wouldn't be able to use a make before break switch to switch between the mains and the battery supply as they wouldn't be electrically synchronised. You'd have to actually break the supply to the load or get something called a static switch which would sync the supplies to avoid dropping the load.

A couple of other things I've come across with battery systems before is be careful as to when the Ah figure is given for, I.e at day one or at the end of their useful life. Secondly it's worth bearing in mind that at the end of the batteries life they'll have to be disposed of, which will I would have thought be chargeable.

Ah, very good tip there mate thank you. As for disposing I would simply sell them on once they stopped holding their charge for a period I was comfortable with, I'm sure someone has a use for these things. Failing that I'm sure disposing of them at a local tip will be a standard fee of some sort.

Unicorn · 29 Jun 2012 at 18:12

Getting rid of the larger batteries is an expensive job i will warn you, 32 Batterys of a similar spec cost thousands per year to maintain with testing and disposal. We use these at work

but they have a nice problem were the terminal heads rise out and cause a nice bang sometimes. Have you taken maintainance costs into account?

snedie · 29 Jun 2012 at 19:36

GrimsbyLAD said:
Getting rid of the larger batteries is an expensive job i will warn you, 32 Batterys of a similar spec cost thousands per year to maintain with testing and disposal. We use these at work

but they have a nice problem were the terminal heads rise out and cause a nice bang sometimes. Have you taken maintainance costs into account?

The batteries I'll be using are sealed, as far as I am aware (feel free to correct me) deep cycle sealed batteries don't require any maintenance, just the regular safety precautions.

If these where lead-acid or some other sort then none of this would be possible even in the slightest. If the deep cycles require maintenance then again, I'll simply abandon the idea.

Fuzz · 29 Jun 2012 at 19:53

Why don't you charge the batteries with solar panels and also use the panels to supplement the electricity you use whilst you are home.
Which for the most part will be morning and evening. The rest of the day you'll be at work and your house will use minimal electricity.

snedie · 29 Jun 2012 at 20:01

Fuzz said:
Why don't you charge the batteries with solar panels and also use the panels to supplement the electricity you use whilst you are home.
Which for the most part will be morning and evening. The rest of the day you'll be at work and your house will use minimal electricity.

Solar panels cost a bomb, you need to have a specific type of roof structure to support them of which we don't have, and also they need regular cleaning to keep their performance above 80%. For me, I would be looking at a price tag of at least £25,000 after having a new roof constructed and panels installed.

If they could generate more than a few hundred watts then I might consider a wind turbine or two, but even those are incredibly expensive and inefficient not to mention noisy (Upwards of 35db just at low speeds).

Another option would be to buy two lots of batteries and charge one set at my work who only pays 8p/KwH (They use a LOT of juice), but lugging 200KG's of batteries to and from work every day would cost a fortune in petrol not to mention be a royal pain in the ass

Fuzz · 29 Jun 2012 at 20:08

You could make your own wind turbine pretty damn cheap to be honest.
No point unless you live in a windy area though of course.

Anyway, back to the solar panels.... Don't put them on the roof then. Install them in the garden.

snedie · 29 Jun 2012 at 20:17

Fuzz said:
You could make your own wind turbine pretty damn cheap to be honest.
No point unless you live in a windy area though of course.

Anyway, back to the solar panels.... Don't put them on the roof then. Install them in the garden.

I'm in a semi-detached terrace row, garden is in shadow most of the day lol