batteries Most economical use of battery storage to heating a room.

[Alshamal]

Had a Lux 9.6 KWh system installed just over a month ago and getting to understand it and making the best of my Go tariff. Was just interested what other more experienced people than me have found the most economical use of the battery power to heat a room? Oil filed radiator/ convection/fan heaters!

we have gas central  heating we use in the most used area of our bungalow but have a TV room which i have to use to watch my Sports 🤷

[JohnMo]

41 minutes ago, Alshamal said:

Oil filed radiator/ convection/fan heaters!

The above all run at 100% efficiency.  So if 9kWh was available you would get 3 hours of heat for one the above rated at 3kW.

 

Something like the below on eBay, would give you 9 hours or more based on the same output to the room and the same 9kWh

 

eBay item number: 195191096004

[SteamyTea]

Well gas is about 10p/kWh.

So divide the cost of your battery system by 10 (it should last ten years.

Then by 5 assuming you need 5 kWh/day out of it. Then divide by the number is of days you want to use it, say 200 a year.

Then add the cost of charging, multiplied by 1.3 to the number.

If that is less than the gas price, plug in a fan heater. If not, use the gas.

[Temp]

21 hours ago, Alshamal said:

Was just interested what other more experienced people than me have found the most economical use of the battery power to heat a room?

 

The amount of energy needed to heat a room depends entirely on the room. How big, how hot, how well insulated, how well ventilated, how long at what temperature etc. If you keep all that constant then it doesn't really matter what type of electric heater you use as they are all 100% efficient. I go for something with a thermostat or timer. Possibly a fan heater if I wanted quick warm up time. Or a convection type with optional fan to reduce noise. 

 

Typically people will say that oil filled heaters cost less than fan heaters but that's normally because they have a lower output so they aren't heating the room to the same standard. 

 

A lot of companies make claims for fancy/expensive "Ceramic core" heaters. Many are frankly dubious, for example some claim the ceramic core continues to give out heat even when they are switched off. That's true but only because the core absorbed energy when it was switched on. Its not free energy. 

 

The only way to do significantly better is to use a heat pump which effectively have an efficiency (COP) of 300%.

 

Edited December 6, 2022 by Temp

[RichardL]

Mini split A2A conditioning/heat pump?  
Heat in the winter/cooling in the summer.

The controls on them are pretty basic + needs a little more infrastructure work to install than plugging in a heater.

[Simon R]

10 hours ago, RichardL said:

Mini split A2A conditioning/heat pump?  
Heat in the winter/cooling in the summer.

We have this setup with a Midea 3.5 kW unit which delivers about 3.5 to 1  and a 9.5kwH battery store. The battery gets charged up over night on the Octopus Intelligent tariff (21:30-5:30) to either 50% if we are expecting sun or 100% for dull days. In our case we run the unit at 22C with a 30% fan rate and it consumes in the region of 500W . Using this setup we use virtually no full rate electricity.  In summer we run the unit to cool when required but it's always running of PV rather than grid.

The split unit was added as an afterthought to help with rather more solar gain than our energy model suggested. It's been brilliant and I wished it had been planned in from the start.

[RichardL]

51 minutes ago, Simon R said:

We have this setup with a Midea 3.5 kW unit which delivers about 3.5 to 1  and a 9.5kwH battery store. The battery gets charged up over night on the Octopus Intelligent tariff (21:30-5:30) to either 50% if we are expecting sun or 100% for dull days. In our case we run the unit at 22C with a 30% fan rate and it consumes in the region of 500W . Using this setup we use virtually no full rate electricity.  In summer we run the unit to cool when required but it's always running of PV rather than grid.

The split unit was added as an afterthought to help with rather more solar gain than our energy model suggested. It's been brilliant and I wished it had been planned in from the start.

++ - Trying almost exactly this principle over the winter with part of the house to get a feel for real world increase in electric vs. decrease in oil in the remainder of the house. Until the cold snap electric was up approx +£10/month,  vs. the usual oil nominal ~£100/month heating spend.

(Different A2A hardware/similar ~500-600w A2A consumption - rising to double that as the temp drops below 0ºC + using Octopus go and the 00:30-04:30 to charge batteries in the winter)

The challenge is extending to a. bathrooms and b. bedrooms
The latter perahps on a separate ducted A2A TBC.

Edited December 11, 2022 by RichardL

[Radian]

I'm heating 60m² over two floors with a couple of mini splits in an outbuilding and I really can't believe how little they cost to run. Keeping the space ticking-over at 18oC used just under 10kWh yesterday with an average outdoor temperature of -1.5^oC Discovering that they can heat the space up by 5^oC in about 20 minutes, I'm going to drop the temp to 15^oC and use the App to boost before I want to use the rooms to save a few pennies. But yes, A2A has to be the best thing to run off batteries.