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Posted 28th Nov 2022 (Posted 23 h, 13 m ago)
Wondering if anyone on here could recommend the most cost effective high output heater. Currently heating an outbuilding which needs at least 8 hours heat per day and using 4kw blow heater. With cost of electric it’s not feasible to continue and hoping someone might suggest something more affordable. The 4kw blow heater just about manages to keep the chill out of the building. I can’t insulate etc so heaters are my only option at the minute.
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    Most electric heaters are more or less 100% efficient. If it’s 4kW you’re putting almost 4kW of heat into that building.

    No matter what you use, you’re going to spend the same amount of money if you really need that much heat.

    There is no easy answer for you. Especially if you can’t insulate or do anything else the best option is to discontinue use of said building to mean heating isn’t necessary anymore.
    This is correct.

    I was of the impression oil heaters were more efficient for a while due to them containing energy in oil but a good video on youtube explained that they just store that same amount of energy but release it slower over time. All made sense when explained clearly.

    The best thing you can do to help reduce the cost is to improve the insulation and block any draught. Any air being able to move in/out is going to have a big impact on your ability to heat a space. High output will allow you to pump out 4kW of heat quickly but you want to make sure as much of that heat is contained so that it can turn off and not need to be on all the time. (edited)
  2. Avatar
    What are you growing
  3. Avatar
    Heat the person not the room? I'm using a usb vest right now.
    Can use a power bank battery but instead I got a USB extension cable and plugged into a USB plug at the mains when not walking around.
    We used electric throws when we lived in Australia. You bake whilst using about 2p per hour
  4. Avatar
    Get an air conditioning unit
    This - air con is an air source heat pump and super efficient for heating with up to 5:1 efficiency.

    Bonus of cool air in the summer too.
  5. Avatar
    How many degrees is it in the building when there's no heating on?
  6. Avatar
    What power sources/fuel do you have access to?

    If it's only electric then you're looking at a heat pump system as none of the systems that convert electricity directly to heat (resistive, infrared etc.) will be more efficient than a fan heater. A clever install may make them feel a bit warmer but if 4kW is barely sufficient now then you're not going to drop below that.

    If you can run a heater on gas, wood or other fuels then that may be a cheaper option.

    Is the insulation limitation a space issue? You can get insulation that goes on the outside of the building as well as the inside. And even insulating just the ceiling even if you leave the walls alone would help.
  7. Avatar
    I would imagine the cheapest way to heat it would be a heater that runs off mains gas. I guess if you happen to use an awful lot of electricity for running machinery etc, then a CHP (combined heat and power) system might be a possibly, where mains gas is used to drive a generator, the heat from it is collected to heat radiators and cheap electricity is produced as a by product.

    One of my father's good friends who lived off the gas grid had a straw burner in his workshop, although it was mainly to provide hot water to heat his house and pool.

    I'd suggest you need to eliminate drafts and do something to improve the insulation. (edited)
  8. Avatar
    The one you dont turn on
  9. Avatar
    Could heat it with a 5kw diesel heater, they use about 0.15ltr of fuel per KW/hr, so 0.75ltr for max output and they can run happily on heating oil, you can buy this from some petrol stations at about a £1 per litre or get a couple of hundred and it's about 85p per litre, so would cost around 65p or 85p per hour for 5kw output.

    I'm swapping out a 2kw fan heater for a 2kw diesel heater, well it's a 5kw one but will run it low power.
  10. Avatar
    based on what you say - and if I had no other option I would be heating the person(s) and not the room. Vest/throw/boots etc all plugged in - cheap as chips and likely feel more benefit
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