All electric heating and hot water

[eddoakley]

Just about to submit a price to convert a pub to 9 flats when the client decides no gas.

Talk to me about all electric options.....who knows what?

I have very limited knowledge and need to learn quickly as I don't want to get this wrong!

 

Edd

[elgreco]

I’m no expert and we are looking to replace our ancient central heating system so have been looking into heat pumps and solar panels. Will be interested to follow this thread 

cheers

Tom

[Yellow Bear]

Heat pumps and under floor heating look the best option.

[Jaymo]

Heatrae Sadia based in Norwich are supposedly the leaders for electric boilers.

Runnimg costs per kw will always be the least economical when using electricity for heating. 
They don’t qualify for the RHI as say, an ASHP would which have a better COP

[Yellow Bear]

3 minutes ago, Jaymo said:

Heatrae Sadia based in Norwich are supposedly the leaders for electric boilers.

Runnimg costs per kw will always be the least economical when using electricity for heating. 
They don’t qualify for the RHI as say, an ASHP would which have a better COP

And ground source even better

[Zapp]

50 minutes ago, Yellow Bear said:

And ground source even better

Ground source heat pumps are an example of clever lateral thinking 

[oldypigeonpopper]

Hello, don't get that electric heating advertised on tv, it's double to run from what is estimated when fitted,

[JohnfromUK]

A few very important things;

1. Per kilowatt hour, electricity (non off peak) costs roughly 5 times gas (gas about 3p, electricity about 15p) - that is a hard place from which to start.
2. Heatpumps are expensive to install (especially ground sourced) ...... and still typically (at present) a bit more expensive than gas to run
3. Heatpumps produce a lower water temperature better suited to underfloor heating than radiators.  Where used radiators need to be much larger.
4. In all cases, very high levels of insulation are needed to control running costs
5. Very high insulation can be difficult in older properties - where the structure and materials may need higher ventilation to control damp.

[Jaymo]

Having had a little sleep to refresh one brain, I have reread that it’s a single building being divided up into flats.

That makes the logistics of ASHP or GSHP rather out of reach, due to siting and noise metering requirements.

So, your back to the Heatrae Sadia type boilers or electrical rads - storage heaters have come along way, but are still not flexible enough for today’s heating/occupancy patterns. 

[eddoakley]

Thanks for the replies so far.

Ground source etc are definitely out.

It seems a choice between electric boilers or individual rads and electric heater for dhw. 

Boiler looks preferable at the moment but need to look into their capabilities re flow rate. 

Looks like no baths and electric showers along side the boiler.

Any more info or advice would be appreciated.

 

Edd

[JohnfromUK]

7 minutes ago, eddoakley said:

Any more info or advice would be appreciated.

I am assuming the property is being done up to either let or sell the resulting flats.  The key question therefore seems to be what the effect of electric options would be on the rental/sale prospects.  A word with estate agents might be sensible?

Opposite me, there is a small development (local authority) of bungalows specifically for rental to the elderly - done some years ago - and specifically 'all electric' as gas was (then) considered a possible hazard for elderly from both burns and leaving gas on unlit.  They developed a reputation of being horrendously expensive to heat - so much so that they struggled to let them, despite being very nice properties in other respects.  Eventually - the local authority relented and installed mains gas (about 10 years ago).  The one opposite me - the occupiers then said that their bills had more than halved and they were much warmer.

Electricity is an expensive energy source - and if you do have to use it - insulation is absolutely essential - along with ensuring that it doesn't become damp due to lack of ventilation.  (Possibly forced air heat recovery?).

But the key question would be what the rental/buy market likes and doesn't like if that is the end purpose.

[Mungler]

I looked at this for my latest project and all the electricians I spoke to laughed and then sent me the prices of the latest electric storage heaters.

I also asked on here and was given the definitive steer to gas.

Indeed, on the maths I can get a full blown combi boiler run central heating system for a 5 bed house for the same cost of 4 of the new fangled electric rads.

Also there was the mains supply issue:

1. Max domestic is 100 amp in and when you write it down on paper it’s not enough -  think the depth of winter, electric central heating on, an electric car charger in the background and someone then making breakfast (kettle and toaster) and someone jumping in the shower would easily pull the lot over.

2. The price of leccy is going to be an issue applying supply and demand - demand is going through the roof and where’s the supply coming from? You can’t throw up a nuclear power station over night 

[JohnfromUK]

7 minutes ago, Mungler said:

The price of leccy is going to be an issue applying supply and demand - demand is going through the roof and where’s the supply coming from? You can’t throw up a nuclear power station over night

Very true, and nor can you up the grid capacity to distribute it all overnight.

The average UK house needs 10,300 KWhr of space heating per year.  On present costs - roughly:

• Normal tariff electricity - £1545 per annum - Low installation costs
• Off peak (with on peak boost) possibly £800 per annum - Medium installation costs
• Electric air sourced heat pump with SPF of 3 - roughly £600 per annum - High installation costs
• Mains gas with 85% efficient boiler - £363 per annum - Medium installation costs

[bavarianbrit]

We had roof mounted solar water heaters installed which transfer the so gained heat BTUs into the hot water tank 15 years ago, it developed a leak after 13 years and the government here Bavaria had a grant scheme to upgrade then anyway so we had it renewed for almost free. In summer it really cranks up the hot water systems temp to uncomfortable levels where you need lots of cold water added to make a shower do-able.

[discobob]

I was just about to add what @bavarianbrit has added - We had it in Cyprus in the 90's and it was pretty basic - a black box with one side glass and a pipe running through it - done all our hot water for 10 months of the year.

So what about Solar electric and hot water along with something like Tesla Powerwalls - expensive upfront but should lower the ongoing costs - and apparently there is a smart tariff from Octopus Energy for charging up the powerwall if needed - will also balance with electric car charging as well

[Jaymo]

If we had the choice then we would have gone mains gas every time.

But the village isn’t supplied so that left oil/lpg or ASHP elec.

oil has a volatile pricing and the siting of tanks under current regs is limited ( yes, bundled fire rated could make it slightly easier but local installers weren’t keen).

LPG tank siting even worse due to siting issues and need to be seen by the delivery driver for top ups.

So, that left us with electricity and an ASHP - the grant we receive from the RHI scheme is worth £1200 per year which offsets the costs involved. 
But start up and install costs were high in comparison to purchasing an oil/gas boiler. 
 

Regarding an earlier comment on 100amp mains head fuse ( could be 60 or 80amp, never assume). There is a formula for calculating ‘Max Demand’ bit most sparkies will tell you that it’s slightly unrealistic as most houses would exceed this. 
But in truth, even with electric rads then they are cycling and not drawing continuously. 
 

I don’t think Solar to supply the demands of a heating system is a realistic proposition 

[JohnfromUK]

35 minutes ago, Jaymo said:

Regarding an earlier comment on 100amp mains head fuse ( could be 60 or 80amp, never assume)

Yes, mine is 80A and that for a large house is nothing these days.  Apparently it cannot be uprated much due to the underground cabling .......

I have electric cooking, and two 'instant' water heaters under handbasins which are 7.5 KW.  So there is the potential to blow the main fuse fairly easily.

37 minutes ago, Jaymo said:

I don’t think Solar to supply the demands of a heating system is a realistic proposition 

Agreed; It can warm water easily in summer - but my gas bill (10 - 15 p daily) for heating the water alone in the summer is miniscule anyway.  In winter, I use maybe 75 to 150 KWhr of gas daily (£2.50 - £5 very roughly) - and solar would not make much of an impact on that.

[udderlyoffroad]

3 hours ago, Jaymo said:

If we had the choice then we would have gone mains gas every time.

But the village isn’t supplied so that left oil/lpg or ASHP elec.

Following this thread with interest as I'm purchasing a place off mains gas too.  Currently heated with storage heaters and an immersion for the hotwater.

Thinking of going solar PV to at least offset the heating bill and some 'smart' e-rads.  Currently looking at hotwater tanks that work better with solar PV (e.g. Mixergy)

 

 

[JohnfromUK]

1 minute ago, udderlyoffroad said:

Following this thread with interest as I'm purchasing a place off mains gas too.

In my view the key things to consider are;

1. How warm you want it and how much (i.e. what may be OK for occasional use isn't so good if in everyday usage).  For example a 'holiday home' used mainly in summer and weekends may be much less critical on running costs than a house where someone is in doing office type work all day.
2. How much insulation can be installed/improved - this is often the very best place to spend the money.
3. The actual cost of 'heat' per KW, which is loosely;

• Gas 3p
• Oil (varies), but 4 to 5p frequently
• LPG 6 to 7p
• Off peak electricity (note that you often pay more for on peak if you have off peak installed) about 9p
• Basic electricity - about 15p  On all electricity types, note that a 100A supply is 20 KW, which is only the equivalent of a fairly modest boiler size.  If you want other electrical services, car charging, cooking etc., think carefully about peak capacity as it is quite limited (and not just by the cost!).  On full use it costs around £3 an hour at 100 Amps.
• Heatpump output based on 3 to 1 gain - approx 5p

Oil, gas and LPG are about 85% efficient, electricity near enough 100%.

One approach which I use is to have a 'basic' heat through the house from central heating that keeps everything aired and in good condition - and local heat (in my case gas fires) where I am sitting for periods).  Radiant heat can provide a high comfort as it 'feels warm'.  This might work well with say a heatpump/underfloor set up to give the background heat and a log burner for sitting by in the evenings.

[old man]

16 hours ago, eddoakley said:

Just about to submit a price to convert a pub to 9 flats when the client decides no gas.

Talk to me about all electric options.....who knows what?

I have very limited knowledge and need to learn quickly as I don't want to get this wrong!

 

Edd

All I can tell you is that I have a close friend who went all electric as you describe, he has spent thousands after the main events (two separate tries to get it right) He wishes he had not gone down the avenue of electric to heat water to be pumped around.

[Remimax]

9 flats on electricity ,going to need your own substation to run that lot.

you need to look at cost of a new supply to feed all that before doing anything else.

M8 converted a 42 bed nursing home into 8 flats all electric scottish power assured him the existing 3 phase supply was big enough .

******** said i and sure enough had to be upgraded big time.

 

19 hours ago, Zapp said:

Ground source heat pumps are an example of clever lateral thinking 

great untill they go wrong which in my experience  seems to have a habit of being too often then it gets very costly on the repairs.

[Mungler]

5 hours ago, old man said:

He wishes he had not gone down the avenue of electric to heat water to be pumped around.

So you mean your mate wishes he hadn’t gone down the Electric Avenue, because it was higher. 
 

 

[old man]

21 hours ago, Mungler said:

So you mean your mate wishes he hadn’t gone down the Electric Avenue, because it was higher. 
 

 

Ha. Ha.

No, It keeps failing repeatedly at great cost he says. First system failed 4/5 years in, second one been a problem from the off? 

[Jim Neal]

Good God!  We're gonna....

Interesting factoid:  Electric Avenue was the nickname for a shopping area in Brixton which was the first street in the area to get electric lighting!