Domestic Generator

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fenhayman

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Ely
Am considering buying a petrol generator as standby.
1950's 4 bedroom standard built detached house. Ideally need sufficient power for freezer, gas heating boiler, electric flue fan for gas Aga, minimum lighting.
No need for electric hob, oven, kettle or iron. Power for PC and tv preferable.
Thinking of 240v and extension leads.
Feasible?
 
Certainly feasible. You need to establish what power those items will consume and buy a genny that will cope with that load continuously. and you also need to consider how you will get power to those items that don’t have a three pin plug. Please don’t consider a lead with a 3 pin plug at both ends as some do. if your central heating or aga run off a permanently wired fused switch box (as most do), this will usually provide the power to the boiler and pumps. What I did was put a single 13 amp socket between the fused switch and the heating wiring box. If the generator is called into action, I simply unplug the whole heating system and plug it into a trailing extension lead from the generator.
With the boiler running and two circulation pumps active it only uses about 260 watts. Adding a couple of freezers and a fridge doesn’t take me anywhere near the capacity of my machine. A plug in power meter comes in handy to establish what each single item consumes.
Alternatively you can ask an electrician to provide a means of switching from mains supply to a generator…
 
It sounds like many of the things you want to power are hardwired in - not on a 13A plug - so extension leads may not work.

You need to connect to house wiring with a switch - otherwise you risk sending a shock to anyone working on downed lines, for example. Also incorporate a light to tell you when the power is back on.

If you have neighbours a silent running model might be appreciated.

Petrol - beware of leaving fuel in for any period - modern petrol is contaminated with ethanol and other things that don't last long. Either run dry after use, or use Aspen - and remember you will need a supply of several litres to run for several hours - with similar storage constraints.
 
Anything is feasible within reason but often not safe. Once you get involved with powering any part of the hardwired installation then you must seek professional advice from someone who can visit your property and size everything accordingly. You will need a changeover switch that takes your supply off the grid and onto your genny and paying close attention to the means of earthing.

A domestic standalone genny will power a few items, for lighting it would be easier just to buy LED lamps and keep them charged or buy a string of site lighting that would plug into the 110 volt output on most gennys, most freezers are ok for many hours providing you don't open the door and with a decent sized genny you could plug your Tv into an extension.

If you want a reasonable genny then look at the diesel Hyundai which come with electric start and for a couple of grand they do a nice 6kW model with a good sized fuel tank, plus if you wanted to you can get them with automatic transfer switch compatibility so on loss of power they start the genny and switch over from grid without you doing anything.
 
Friend of mine has the Hyundai electric car and it has a 240v plug socket that can do up to 15A. It's a cool little upside that in a power cut he has a massive battery sat on his drive that he can plug stuff into.
 
The first thing to determine is how many amps you need, so you can get a genny of the right size.
Small petrol gennys are ok, but over about 4 Kw, you may be better off with diesel.
Then there is a question as to where the genny will be located. If it's close to the house, consider the noise factor. If it is some distance from the house, you need to ensure your extension leads are sized correctly. Heat build up and voltage drop often occurs with undersized wiring.
You might consider running heavy fixed wires ( in conduit ) from the genny to the house ( a dedicated power point - suggest a different colour ) and not having unsafe extension cords.
I would also suggest you ensure the genny is earthed.
 
You might need to take the startup spike into account (that probably has a better name for it). If I try to run my 1.8kW log splitter on my 3kW generator then the startup spike exceeds the rating of the genny and it cuts out. I’m given to understand, and I’m most certainly not an expert, that this mostly applies to motors and suchlike and isn’t a problem with lighting.
 
Can you use Red Diesel in a home genny?
Unless you have a genny with wheels that can be driven on the road then no reason why not, but whether you can get hold of it is another question because part of the governments race to carbon neutral is to ban red diesel for many applications but nothing stopping you using normal DERV. So what they are really saying is we sort of care about pollution but getting the duty is more important.
 
Unless you have a genny with wheels that can be driven on the road then no reason why not, but whether you can get hold of it is another question because part of the governments race to carbon neutral is to ban red diesel for many applications but nothing stopping you using normal DERV. So what they are really saying is we sort of care about pollution but getting the duty is more important.
Why not in a towed Genny?

Obvs not in a diesel truck but a towed Genny why not?

It would have to share a tank with the vehicle for it to be illegal??
 
I've got a 4kva Honda on some wheels which I have used a few times when the power goes down here, it will run most things that you will need apart for your electric cooker, but a microwave is just fine. My fridge freezer is run of solar and wind feeding a battery and small inverter. As mentioned you will need to sort out the wiring for the boiler , but well worth having a back up genny, yes a derv geny is better but not worth the extra cost in my view.
 
Ideally need sufficient power for freezer, gas heating boiler, electric flue fan for gas Aga, minimum lighting.
No need for electric hob, oven, kettle or iron. Power for PC and tv preferable.
Thinking of 240v and extension leads.
Feasible?
Yes. That lot sounds like it will barely add up to a kilowatt. A 2kW portable genny would probably sort you out. I'd be looking for a compact quiet suitcase type that starts reliably. I'd put it outside the back door of the kitchen and stick the extension lead through the catflap.
DO put the essential services on three pin plugs so you can shift them to the extension lead.
DON'T think about trying to feed into the household wiring unless you are willing to spend serious money on an electrician to rewire the house to do this safely. Many electricians won't have done this before so choose carefully if you go that route.
I'd make do with a standard lamp or two for lighting. It will be enough and there are multiple issues if you start messing with your lighting circuits.

Unless you live in the sticks, I imagine power cuts aren't long and frequent. No need to go overboard.
 
Thanks for all the useful replies. Am thinking that a 2kw genny may suffice but am concerned (ignorant about) power surges when appliances start up.
Will only use extension leads. No noise problem with leads through cat flap. Only appliance hard wired is gas boiler, guess I can feed that from 13 amp socket. if necessary.
 
Buying a small 2Kw genny is rather limiting it's uses. A small electric heater or a kettle consumes 2.2 Kw so I would either buy something with a little more output or not get to worried about the potential risk of powercuts. Resistive loads are not a problem but anything with a motor like a fridge / freezer compressor will draw more on startup but is not a continous load once down to temperature.

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Before worrying about what generator and how it is connected, I suspect the first task is to understand what you want to back up and for how long.

Covering a full domestic requirement for any length of time needs serious power, proper installation, lots of money.

Covering a limited duration power cut can be dealt with by small generator or battery back up linked directly to low consumption appliances standard lamps, microwave, TV. Cooking could use a simple camping gas if needed.

Fully charged batteries on stand alone lamps, laptops, smartphone will maintain functionality although it may be cold.

Final option - Premier Inn or Travel Lodge who still have power on. Hot meals, showers, bed.

It happens that infrequently in most of urban UK that spending £10k++ for an all singing all dancing solution seems profligate unless the need is critical (eg: kidney dialysis).
 
I have a 3kva petrol generator while it is sufficient for the house during power cuts it will not run the compressor in my workshop. Looking to get a larger diesel one with self start and a link so if the power goes out it will switch automatically. The Hyundai one looks promising But they won’t deliver offshore. Have a look at the weather in Shetland at the moment it’s a bit rough.
 
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