Power cuts & Generators.

[frankc]

Hi guys

like many others i experienced power cuts over the last week. It is quite difficult for us because my wife is in a wheelchair and gets cold real quick. So the thought of buying a portable generator to run a few lights and heating devices sprung to mind.

The easiest way (I assume) is to buy a small 2kw generator. Stick it outside and run an extension lead into the house to run a fan heater and a bedside lamp until the power comes back on.

However the ideal situation would be to find someway to run a household light and the fuel oil central heating boiler. But how practical and expensive would this be? I am not worried about fridges or anything else really. Just a bit of heat and light.

So how much for a small 2 bedroom bungalow backup power?

Any help/suggestions would be appreciated. Treat me like a complete novice and you wont be far off

P.s I have looked at previous posts but they did not help much.

 

[ericmark]

There are a number of ways to use a generator but to use one to directly heat is not really going to help much. The calor gas heaters would work far better.

However to keep light and heat going does not require a generator. One can buy an UPS that is an interrupable power supply which could maintain the supply to a central heating boiler but the question is for how long.

Lights are easy I have emergency lights which as standard work for 3 hours but to increase that time is not really a problem.

Generators make noise and also require some one to start them and put them on line. Where with battery backup it can be automatic.

My son had a boat and could run central heating from a battery for about 5 days without starting the generator with 330 AH of batteries but normally one would not have such a big bank.

However if you use 12v then one can always use the car to charge them.

Generators are great when you want to run one item. However when you want to run more than one item there are some dangers. To avoid these one needs earth rods and some way to distribute the power. Very quickly instead of the £200 for a generator one is looking at over a £1000. The generator is only one cog in the system.

So step one is to find how much power your central heating requires? Then start looking at UPS. But I found having a gas fire fitted was easy and cheapest method. Also good if anything else goes wrong with central heating. Then I installed emergency lights. The latter was in the form of a kit. This mean the light looks normal and I also have more battery power will run for around 6 hours.

The auto touches are also good. When plugged in they auto switch on with a power cut. But unlike the emergency lamp you can turn them off so saving the battery for latter.

 

[frankc]

There are a number of ways to use a generator but to use one to directly heat is not really going to help much. The calor gas heaters would work far better.

However to keep light and heat going does not require a generator. One can buy an UPS that is an interrupable power supply which could maintain the supply to a central heating boiler but the question is for how long.

Lights are easy I have emergency lights which as standard work for 3 hours but to increase that time is not really a problem.

Generators make noise and also require some one to start them and put them on line. Where with battery backup it can be automatic.

My son had a boat and could run central heating from a battery for about 5 days without starting the generator with 330 AH of batteries but normally one would not have such a big bank.

However if you use 12v then one can always use the car to charge them.

Generators are great when you want to run one item. However when you want to run more than one item there are some dangers. To avoid these one needs earth rods and some way to distribute the power. Very quickly instead of the £200 for a generator one is looking at over a £1000. The generator is only one cog in the system.

So step one is to find how much power your central heating requires? Then start looking at UPS. But I found having a gas fire fitted was easy and cheapest method. Also good if anything else goes wrong with central heating. Then I installed emergency lights. The latter was in the form of a kit. This mean the light looks normal and I also have more battery power will run for around 6 hours.

The auto touches are also good. When plugged in they auto switch on with a power cut. But unlike the emergency lamp you can turn them off so saving the battery for latter.

Thanks for that. I have already worked out I can use a torch and a calor gas heater in a power cut But I am talking about a backup power supply and mainly its the heating I am concerned with. Ideally I would like to be able to go outside start up/switch on something and get the central heating working again. Our supply is out for anything from 1 to 8 hours. At the worst it was off for 3 weeks! (we had to move out to a friends house)

Glad I can buy a UPS as a backup for my power suppyly, if only I knew what a UPS was! Is it a battery of some sort? How big is it? Expensive to buy or fit? Universal Power Supply??? Shall have to google it. Dont worry I have worked out already that its not a United Parcel Service.

Thanks again for taking the time to reply.

 

[frankc]

I have just looked up a UPS I cannot see them being of any use to me. I am not really interested in stopping the interuption just restoring the central heating boiler and a light.

I was thinking of putting up an out door plug. Putting a cable through the cavity wall and up into the attic. Across the attic. Down the cavity to emerge next to the boiler then attach socket for a plug to that. Swapping over the fixed mains wiring of the boiler with a plug and socket. So that if the power does go out I can unplug the boiler from the mains supply and plug it into the backup socket. Go outside and start the generator. Plug the power supply from the generator into the outdoor socket thus being able to power the boiler from that. At the moment we have a worcester bosch boiler Heatslave 12/14, but I dont know how much power the generator needs to push out in order to power it. Thoughts?

 

[bernardgreen]

What you need for the heating is an SPS ( Stanby Power Supply ) or inverter that will provide you with mains voltage with an approximately correct sinewave form. These run from a 12 volt battery and have a 13 amp socket. They will not provide 13 amps ( 3 Kwatt ) but depending on type up to about 300 watts.

A UPS for computors is NOT suitable for the central heating as the wave form shape might be a square wave ( not sinewave ). Computor power supplies are OK with a square wave but the central heating pump motor and the fan in the boiler may not work properly with a square wave mains input.

Then you have the problem of how to feed the central heating system with power from the SPS. If the heating runs from a single 13 amp plug then simply plug that into the SPS. IF it doesn't then you will need an electrian to arrange a means to connect the SPS to the heating.

You can buy SPS invertors that run on 24 volt and require 2 car batteries. These are more efficient but require a 24 volt charger or charging the batteries in turn. 12 volt invertors for domestic use have the advantage that in a prolonged power cut with a set of long heavy current leads you can run from the car battery with the engine used to recharge that battery.

 

[frankc]

Thanks. Back to Google to find out what a sps inverter is

 

[frankc]

Something like this? clicky here

 

[pjcomp]

Most UPS you find will have been designed with computers in mind, particularly emergency back-up for file servers: power goes, UPS battery keeps the server going long enough for a controlled shutdown to avoid corruption of open data files.

For a generator to take over your household power you will need a suitable switch - Briggs and Stratton produce one for around £230. It is fitted in to your supply feed so that in normal operation the Grid power comes in in the normal way. In the event of a power cut you switch to the centre position (neutral), start the generator, then switch over to generator position, and the genny is now feeding the power into the installation.

How much can actually be run from it will depend on the size of generator used, but the basics like boiling a kettle and running the central heating should be covered.

The reason for the "break before make" of the switch is so that your power can't feed back into the grid just when some unfortunate engineer is trying to fix things at teh sub-station!!

Fitting the switch is not a d-i-y job.

PJ

 

[bernardgreen]

That is the sort of unit you need. It is claimed to work with inductive loads ( transformers ) Check with the suppliers what derating if any is needed when supplying an inductive load ( pumps and fans are inductive loads ). For 150 watts of inductive load you may need a 300 watt unit.

 

[ban-all-sheds]

I was thinking of putting up an out door plug. Putting a cable through the cavity wall and up into the attic. Across the attic. Down the cavity to emerge next to the boiler then attach socket for a plug to that. Swapping over the fixed mains wiring of the boiler with a plug and socket. So that if the power does go out I can unplug the boiler from the mains supply and plug it into the backup socket. Go outside and start the generator. Plug the power supply from the generator into the outdoor socket thus being able to power the boiler from that.

NO!

You must not do that.

The cable you describe from the generator to the socket is known, with good reason, as a "widowmaker". The pins of the plug will be live - it's very dangerous.

If you want to plug the generator in like that then you must use an inlet on the house, not a socket, and a female connector on the end of the cable from the generator, not a male plug.

 

[DetlefSchmitz]

I didn't read what OP said that way. It was a bit loose, but didn't seem not to suggest bringing power out of male connector.

 

[ivixor]

The way I understood it the OP was (in a roundabout way) describing a extension lead.

One end with a plug goes into the generator, the other end terminates in a socket to which you plug the boiler during a powercut. Sounds safe to me, although running cables in cavity walls isn't a good idea.

 

[efiste2]

100% echo PJcomp's comments about accidental back feeding the DNO network. seen many double 13A plug top leads next to portable gennerators where consumers have regular power cuts and and blissfully unaware of what theyre doing!!!.....make sure any generator you connect is competely islanded from the netowrk by a suitable changover switch

 

[pjcomp]

Re the extension lead idea - a generator produced for domestic type use sometimes has a socket built in. Extension lead plugs into socket the same as it would into a wall socket, in through the window and plug in the kettle. Appliance - lead - genny, no conenction to the installation. Had a customer who kept her home business (computer, printer, internet access) running like this while we turned off the power to rebuild her house around her.

PJ

 

[ban-all-sheds]

I didn't read what OP said that way. It was a bit loose, but didn't seem not to suggest bringing power out of male connector.

The way I understood it the OP was (in a roundabout way) describing a extension lead.

One end with a plug goes into the generator, the other end terminates in a socket to which you plug the boiler during a powercut.

OK - it's quite possible I misinterpreted this:

if the power does go out I can unplug the boiler from the mains supply and plug it into the backup socket. Go outside and start the generator. Plug the power supply from the generator into the outdoor socket ....

But if not then he's had a timely and valuable warning.