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  1.  
    Hi All,

    A friend of mine is looking to replace his old storage heaters with new ones.

    He has had Fischer out and in my view the quote is mind boggling!!

    The quote comes in at 10k for direct replacement units at 1.3kW each.

    Each heater is £1534 before a small discount!!!

    I understand that these are German and have remote stats but the price seems absurd to me.

    Does anyone know about this type of heater or Future Heat UK?

    I have tried discussing other systems with him but as yet to no avail.

    Many thanks.
    • CommentAuthorCWatters
    • CommentTimeJan 17th 2017
     
    I'm not 100% sure but I don't think Fischer storage heaters are the same as traditional night storage heaters.

    http://www.fischerfutureheat.com/electric-heaters/electric-storage-heaters/

    eg I don't think they are designed to store energy at night and emit it during the day. They are more like instant heaters with a bit of storage to smooth energy delivery. So I think they will be darn expensive to run as they will mostly use peak rate electricity to heat the house in the daytime.

    Their web site says..

    "The actual input is regulated by the room thermostat thereby heating the Fischer heating clay core as desired, depending on the weather and the desired setting in the room, giving you complete control of each room’s temperature and you can still benefit from the cheaper electricity rate during the night using economy 7."

    ..but I think that means it uses E7 to heat the room at night and peak rate during the day. I don't think it means it stores enough E7 energy at night to last during the day although it might store a little. The give away is that there doesn't appear to be any insulation in the heaters to prevent it heating the room immediately.

    Also don't be fooled by words like "low input". If your rooms are heated to your satisfaction then the cost (amount of energy needed to heat your house) depends on how well insulated it is, not how powerful the heater is.

    I don't see much advantage to a Fischer compared to something like a Dimplex or even a fan heater.

    I might be wrong but you should double check.
    • CommentAuthorgravelld
    • CommentTimeJan 17th 2017
     
    Check out the MoneySavingExpert forums - Fischer are discussed often there. They are the Anglian Windows / Safestyle / Dolphin Bathrooms / Moben / Sharps of electrical heating.
    • CommentAuthorskyewright
    • CommentTimeJan 17th 2017
     
    If your friend wants to see some more sensibly priced storage heaters, from classic dumb ones (the sort I prefer, 'cos I get to decide what they do & when) to programmable 'smart' ones, take a look at the Elnur range that TLC Direct do.

    https://www.tlc-direct.co.uk/Main_Index/Heating_Index/index.html
    • CommentAuthortony
    • CommentTimeJan 17th 2017
     
    Direct electric is 100% efficient night store less so but uses cheaper electricity

    However an air source heat pump is 350% efficient, yes you debt 3.5 kW of heat from each kW of electriciry

    At the point of spemding money this is a good time to make decisions.
    •  
      CommentAuthorSteamyTea
    • CommentTimeJan 17th 2017 edited
     
    Right, let us get a few things straight.
    An electrical storage heater will have thee parts that are important.
    The storage capacity in kWh
    The charging rate in kW
    The discharging rate in kW or time.
    The discharge rate is less than the charging rate (I could go into this but not really necessary for this enquiry).

    They are, in effect, 100% efficient i.e they release all the electrical energy put into them as thermal energy, regardless of when they are charged up and what type of tariff they are on.

    More modern storage heaters have better insulation and often some sort of electro-mechanical control. This allows better control of the discharge rate. They tend to be a bit smaller as well.

    If your friend was happy with his old storage heaters i.e. they kept the place warm, a simple upgrade to some with better controls on them will be all that is needed. No need for new wiring as they will have the same power rating.
    It may be worth checking that all the electrical elements are working in them. There is usually 2 or 4 elements of about 750W each. The easy way to check is to place your had on the front, if there is a cooler area, then an element has failed. They are easy to change (two screwdrivers and some oven gloves).

    Like most heating systems, they usually cannot cope with very cold weather, so it is usual to have a panel or fan heater as a back up. But that is more to do with the heat losses from the house rather than the type of heating system.
    •  
      CommentAuthorfostertom
    • CommentTimeJan 17th 2017
     
    Posted By: SteamyTeaThey are, in effect, 100% efficient i.e they release all the electrical energy put into them as thermal energy
    Should read:

    "They are, in theory, 100% efficient i.e they release all the electrical energy put into them as thermal energy -
    but in practice considerably less efficient because so much of the thermal energy is released at night when it's no good to anyone and might as well not exist."
  2.  
    Thanks all.

    I agree with the comments and I understand the HP gains to be made if installed.

    I would consider the ASHP but he can't fit UFH as he has no insulation in the house under floor.
    The property is a small, lovely fisherman's cottage in west Wales. This may be an option with rads though albeit with lower flow temps.

    In my opinion I would just change the heaters like for like and save the best part of 7k.
    I just don't see how these heaters will benefit him.

    I am a bit annoyed as the salesman gave him the patter and he is 70 years old.
    •  
      CommentAuthorSteamyTea
    • CommentTimeJan 17th 2017
     
    Consider some A2AHPs, maybe with some extra panel heaters and a constant review of electricity tariffs.
    http://www.appliancesdirect.co.uk/p/eiq-9wminv/electriq-eiq9wminv-air-conditioner?refsource=Apadwords&gclid=CMSCs8TKydECFUcQ0wodXuIP9Q

    Posted By: fostertombut in practice considerably less efficient because so much of the thermal energy is released at night when it's no good to anyone and might as well not exist.
    Umm, isn't that rewriting the laws of thermodynamics to suit an anthropological viewpoint.
    In this house we obey the laws of thermodynamics.
    Not something I would expect from someone that likes to think that mass can store enough energy to heat a place during the winter.
    • CommentAuthorEd Davies
    • CommentTimeJan 17th 2017
     
    Posted By: SteamyTeaUmm, isn't that rewriting the laws of thermodynamics to suit an anthropological viewpoint.
    Any definition of efficiency will be written to suite an anthropological viewpoint; it's how one works out what's useful energy and what's free input or waste output.

    On the other hand, shouldn't new storage heaters have good enough insulation that very little energy gets wasted overnight and better controls so they don't heat unnecessarily during they day? Still not 100%, though.

    Modern storage heaters which are clever enough to charge from PV as well (maybe once the DHW's done) seem like a pretty good idea to me. Those Fischer things don't look like that at all and if they're significantly better than a simple radiant heater then they don't make the advantage obvious of their web site.
    •  
      CommentAuthorfostertom
    • CommentTimeJan 17th 2017
     
    Posted By: Ed DaviesModern storage heaters which are clever enough to charge from PV as well (maybe once the DHW's done)
    Now yer talkin' - excellent. Electric Agas too.

    Posted By: SteamyTeamass can store enough energy to heat a place during the winter
    But not all of the incoming energy, assuming you mean the building fabric mass's ability to store energy that's arriving to it from storage heaters, out-of-sync with immediate need.

    That energy stores into the fabric mass partly by direct radiation from the hot casing.
    It may also store inward into the fabric but only when overnight air temp exceeds the fabric's i.e. air temp higher than daytime comfort temp when the fabric emits outward.

    Elevated overnight air temp is uncomfortable, likely to be ventilated away, meanwhile will be lost by increased fabric loss.

    So no way is all the out-of-sync heat emission usefully stored by the fabric - much is deliberately or passively disipated.
    • CommentAuthorskyewright
    • CommentTimeJan 17th 2017
     
    Posted By: gustyturbine
    In my opinion I would just change the heaters like for like

    That's how I came across the Elnur's at TLC.
    Two of our 20 year old Creda's were looking rather tatty. The Elnurs were straight replacements (though the single element bathroom one was better than the original as the new one has a usable output control!).

    N.B. When we bought (& when I last looked) TLC deliver the Elnurs FOC (even to here) - that's very good as there can be quite a stiff delivery charge for storage heaters.
    • CommentAuthorskyewright
    • CommentTimeJan 17th 2017
     
    Posted By: Ed Davies
    On the other hand, shouldn't new storage heaters have good enough insulation that very little energy gets wasted overnight and better controls so they don't heat unnecessarily during they day? Still not 100%, though.

    The TLC site has some quite detailed brochures for download that illustrate levels of insulation & air flow paths (the air flow paths for 'old fashioned' passive (i.e. just radiation & convection) storage heaters and the more modern fan assisted or 'smart' heaters are different).
    •  
      CommentAuthorSteamyTea
    • CommentTimeJan 17th 2017
     
    Posted By: fostertomout-of-sync with immediate need
    Don't that depend on peoples lifestyles though.
    If a call centre, say for the emergency services, is working at night, then there is no 'out of sync'.
    The efficiency, the ratio of energy in to energy out, will be the same.

    A storage heater should reach peak temperature, and therefore maximum storage, just as it switches off at the end of the metering period (7 AM where I am). This coincides nicely with some of the coldest time of day. Or just when you need a bit more energy. Come the end of the day, they are cooler, but the ambient air temperature is warmer, so they can still deliver useful power without a serious temperature variation.
    If they are sized correctly (for the building) and used correctly (even the old ones have at least 2 settings, storage temperature and air flow control), they should not give a problem.
    But like using a normal thermostat as a switch i.e. totally off or maximum on, most people do not adjust storage heaters when they should.
    If the house is too hot in the morning, then turn the airflow control down before bedtime, that is what it is there for.
    If the storage heater are too cold at night, turn the storage temperature up, that is what it is there for.
    It really is not that difficult.
    •  
      CommentAuthordjh
    • CommentTimeJan 17th 2017
     
    Posted By: fostertom
    Posted By: SteamyTeamass can store enough energy to heat a place during the winter
    But not all of the incoming energy, assuming you mean the building fabric mass's ability to store energy that's arriving to it from storage heaters, out-of-sync with immediate need.

    That energy stores into the fabric mass partly by direct radiation from the hot casing.
    It may also store inward into the fabric but only when overnight air temp exceeds the fabric's i.e. air temp higher than daytime comfort temp when the fabric emits outward.

    Elevated overnight air temp is uncomfortable, likely to be ventilated away, meanwhile will be lost by increased fabric loss.

    So no way is all the out-of-sync heat emission usefully stored by the fabric - much is deliberately or passively disipated.

    I do as much of my heating as possible overnight and almost all of it is 'stored' in the fabric of the building. So I call bullsh*t. I don't open any windows and only open doors to go through them, and the house is very comfortable thank you. I did worry at the start that we'd get too hot at night, but it isn't actually a problem. We did have to return one very expensive duvet (the wife is peculiar but not unusual in liking 'luxury' rather than performance) but they replaced it with a lower-TOG version so all was not lost.

    When I started on my house design journey, I was thinking of using a 20 m³ water storage tank within the building to provide seasonal heating (space & DHW). There's no difficulty in getting appropriate heating power from it during winter without venting. I think FT is neglecting the long time constant of well-insulated buildings in his thinking. The cost and complexity is what put me off a seasonal heat store.
    • CommentAuthorEd Davies
    • CommentTimeJan 17th 2017
     
    But Dave, we're likely not talking about a well-insulated building here, however lovely it is. A significant part of the heat released overnight will be lost before morning.

    Posted By: gustyturbineThe property is a small, lovely fisherman's cottage in west Wales.
    •  
      CommentAuthorfostertom
    • CommentTimeJan 18th 2017
     
    Posted By: djhI do as much of my heating as possible overnight and almost all of it is 'stored' in the fabric of the building
    So if the building is highly insulated, has thermal massiveness properly sized and arranged, and no one minds the hottest air temps being overnight and doesn't regard that as unnececessary, then night storage heaters can be said to not 'waste' any of their energy input.
    •  
      CommentAuthorSteamyTea
    • CommentTimeJan 18th 2017
     
    Posted By: fostertomand no one minds the hottest air temps being overnight
    If properly sized and used, then this is a non issue.
    If incorrectly sized and used, then it may me. But that is true for any heating system.
    • CommentAuthorsnyggapa
    • CommentTimeJan 18th 2017
     
    It would be interesting to know what the annual electricity bill currently is and the split between day and night usage.

    And I would also look at an air/air heat pump depending on the layout - if it's something approaching open plan then that could work really well

    My for well insulated property we have a wood stove and direct electric panel heaters, nobo series 8. Cheap,, programmable/controllable and relatively unobtrusive - but since our heat demand is low the use of peak electricity isn't a problem. If his heat demand is high, then load shifting into E7 or usage of a heat pump to multiply the effect is much more beneficial.

    -Steve
    •  
      CommentAuthorfostertom
    • CommentTimeJan 18th 2017
     
    Posted By: SteamyTeaIf properly sized and used, then this is a non issue
    Really? That's impressive if really so - things have moved on. Hard to believe that any insulation can be that effective, surrounding a core at really high temp. What kind of insulation is used?

    Mind you, AFAIC night time room temps should be not merely extra-high, but considerably lower than daytime. To me, that's comfortable, higher is sweaty, however lo-tog the duvet is. Anything higher that 'lower' I'd consider wasteful use of input energy.
    • CommentAuthorringi
    • CommentTimeJan 18th 2017 edited
     
    Firstly storage heaters need additional quick acting heaters for when there is a cold evening (log burner?, otherwise you will be storing too much heat most of the time. You also need to know how to control them, lots of people keep changing the input controls based on what heat the wanted the heaters to have stored the night before!

    Then consider how the building is used, if you are out at work all day, storage heaters are not a good option, as they give out some heat all day, but for retired people they can work well.

    When I lived in Cambridge I had two storage heater (living room & landing) along with gas fires in each room, I used the storage heaters to provide a little background heat, they work well for that, however without the gas fires I would not have liked the storage heaters. As the gas fires did not have thermostats, they could not be left on overnight or when I was at work, hence the gas fires without the storage heaters would have been harder to control.

    (Before moving and renting out the property, I had gas CH installed, so the tenants got a lot better system then any home owner had living in that property!)
    • CommentAuthordickster
    • CommentTimeJan 19th 2017
     
    We occasionally get junk mail adverts for an amazing new way to heat your house with electricity. Very nice literature and very glossy paper selling this remarkable new revolution in heating, but what is in reality just a nice looking modern storage heater.

    I suspect the cost is astronomical compared with a heater of the shelf. Pity the poor (and probably elderly) people who take this bait.
  3.  
    How much would a domestic battery store and cost?
    • CommentAuthorCWatters
    • CommentTimeJan 19th 2017
     
    Posted By: dicksterWe occasionally get junk mail adverts for an amazing new way to heat your house with electricity. Very nice literature and very glossy paper selling this remarkable new revolution in heating, but what is in reality just a nice looking modern storage heater.


    Most of those that we se aren't actually storage heaters, just direct heaters. One company claimed their electric rads had a running cost about half that of Natural Gas. I filed a complaint with the ASA about that and it was upheld. Another company web site claims that convection heaters need 33% more energy to "heat a room" than their Infra Red heaters.
    •  
      CommentAuthorSteamyTea
    • CommentTimeJan 19th 2017
     
    Posted By: CWattersAnother company web site claims that convection heaters need 33% more energy to "heat a room" than their Infra Red heaters.
    Not getting into that one :devil:

    What is really happening with these sorts of adds is that they are relying on people not understanding an electricity bill.
    This is a real shame as they are basically pretty easy to work out.
    It may account for being laughed at when I suggested a course on 'Understanding Energy'. The same kind of course can be run on phone bills and personal finance. Shame as most people can easily understand this stuff, but just don't want to spend 2 hours on it.
    • CommentAuthorCWatters
    • CommentTimeJan 21st 2017
     
    Physics should be compulsory in schools.
    •  
      CommentAuthordjh
    • CommentTimeJan 21st 2017
     
  4.  
    quote Cwatters
    ''Physics should be compulsory in schools.''

    I never understood physics at school. It was not till I started 'doing' (building) physics (and indeed motorcycle physics) that it made any sense.
    •  
      CommentAuthorSteamyTea
    • CommentTimeJan 21st 2017
     
    They could teach Physics in History lessons if they wanted to. Would be much more interesting learning about Scientists and what they achieved, rather than Kings and Queens of England between 500 and 1500 BC (as I had to).
    •  
      CommentAuthorfostertom
    • CommentTimeJan 21st 2017
     
    Posted By: SteamyTeaKings and Queens of England between 500 and 1500 BC
    For that, you'll have to consult Michael Morpurgo
   
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