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What Impact Will Decarbonising Heat Have On Power Demand?

October 16, 2019
tags: , ,

By Paul Homewood

 

 

There has been some discussion about the impact of decarbonising heating, in terms of the impact on the electricity grid capacity.

Perhaps the best place to start is the following chart, which was included in Lord Oxburgh’s report on decarbonising to Parliament in 2016:

image_thumb-129

https://notalotofpeopleknowthat.wordpress.com/2019/02/22/why-lord-oxburgh-ruled-out-electrification-of-heat/ 

 

If all heating was to be electrified, we would need maybe an extra 350 GW of power capacity to meet peak demands in winter, seven times as much as we have now. Not only would this entail the construction of huge amounts of new generators (which would stand idle for most the year), but also a massive upgrading of distribution networks.

Heat pumps, of course, have a higher efficiency than direct heating, perhaps three times as much. So if they were used to replace current gas central heating we could be looking at maybe 100 to 150 GW extra capacity needed. There again, heat pumps become much less efficient as outside temperatures drop, so the true figure will lie in between, as the CCC explain:

image

https://www.theccc.org.uk/publication/hydrogen-in-a-low-carbon-economy/ 

 

There is also the problem that heat pumps cannot provide the sort of instant heat that gas can, so won’t be of much use on cold winter mornings.

The alternative to heat pumps is hydrogen, produced from natural gas via steam reforming. However this is an extremely costly way of replacing gas, both in terms of hydrogen production and converting household appliances and pipes.

Worse still, the process produces CO2, which therefore needs to be captured at great cost. Even then, some CO2 emissions still occur.

In their infinite wisdom, therefore, the CCC have come up with the cunning plan of combining heat pumps with hydrogen in a hybrid system:

 image

https://www.theccc.org.uk/publication/hydrogen-in-a-low-carbon-economy/

In winter months, heat pumps provide a steady background heat, but the hybrid boiler kicks in to give a boost at times when extra heat is needed. This way, the extra demand put on the grid is around 50 GW.

Based on this and expected demand from EVs, the CCC are projecting peak demand of 150 GW by 2050.

66 Comments
  1. Joe Public permalink
    October 16, 2019 6:52 pm

    Meeting heat demand is very inflexible to time-shifting.

    This animated vid by the University of Birmingham shows hourly data used for the comparison between gas and electricity in Great Britain. It shows the scale of the challenge and opportunities. Note: ‘Local’ gas demand does not contain large industrial, large gas power stations, gas to storage or exports.

    It fails to mention that over the year, ~40% of the electricity generation shown is generated by most of the gas that’s NOT shown – i.e. the electricity generated by gas!

    The real challenges, that TTBOMK have not been answered, are how will peak-hour, peak-day, max 1-hour and max3-hour ramp-rates be met?

    We’ve just 33GWh of electricity storage – 27GWh pumped hydro plus ~6GWh of batteries. Sufficient only for about 45 minutes of our *existing* January cold-weekday demand.

    • Steve permalink
      October 17, 2019 7:43 am

      The real challenge would be to supply enough electricity and hydrogen to keep heating and transport going over a few weeks wind lull in freezing mid winter. Also, liquifieng hydrogen is very energy intensive. No wonder the hydrocarbon lobby is pleased with this and note that they plan to only keep a couple of nukes going- so even more gas from Russia and the ME

      • Gerry, England permalink
        October 17, 2019 1:58 pm

        Maybe the real challenge is actually being able to pay for all this lunacy. With electricity costs steadily rising how many will be able to afford to run a heat pump if they have one? The departure of manufacturing elsewhere will bring unemployment, lower tax revenues and higher benefit payments so less taxpayer cash for the government to waste. Will they have enough gas left to burn the bodies of those who freeze to death every winter as they have to spend on food not heat?

  2. October 16, 2019 6:57 pm

    Reblogged this on Climate- Science.press.

  3. Chris Reynolds permalink
    October 16, 2019 7:00 pm

    Has anyone determined what proportion of the existing housing stock can be retro-fitted with heat pumps?

    • MrGrimNasty permalink
      October 16, 2019 7:21 pm

      It’s completely impractical – e.g. in Australia there are very strict rules on air conditioning units (heaters and coolers) and hours of operation to avoid noise nuisance – essentially no measurable noise (above background) at night.

      There is no way these necessary rules could be complied with in the UK with our dense housing stock. The type of low-level but unremitting brain-gnawing noise these air-source heat pumps produce will drive the population nuts.

      It’s the same as the fact that nobody has actually considered what it will be like when every car has to be plugged in to a phone-box sized fast charger with a flying lead over the pavement. You already can’t use the pavement a lot of the time for all the recycling bins!

      They just have blind faith that somehow all this nonsense will just fall into place.

      PS: I see Monbiot got his wish to be arrested fulfilled. What an idiot.

      • Steve permalink
        October 16, 2019 9:15 pm

        I live in the constituency of the Chief Green loon and have never met anyone in Brighton who talked any common sense in engineering . If Paul could pass my email to you, perhaps we could meet.

      • HotScot permalink
        October 16, 2019 9:43 pm

        MrGrimNasty

        Good points, well made.

        Air Source Heat Pumps (ASHP) are seen to be the quick and easy solution but they are as expensive as Ground Source Heat Pumps (GSHP). ASHP’s are easier to install but I believe less efficient as the temperature falls. There is less heat in the air to be extracted. GSHP’s whilst more efficient thanks to the subsurface temperatures being relatively stable at around 14C from memory, requires a large garden to be completely excavated to run, perhaps, 50m to 100m of pipe up and down the garden before being covered to a depth of around 1m.

        The real problem with both is that they rely on the house being almost airtight and very well insulated, which is fine with new builds and builders turning (only now) to Structurally Insulated Panels (SIP) which are basically two sheets of ply with a rigid foam core bonding them together.

        But much of UK housing stock is very old, much of it with Victorian, solid masonry walls. One would have to add insulation to every wall, in every building, essentially constructing a house within a house, then there’s the floors, ceilings, as well as specialist windows and doors.

        The problem is then, dampness. With no natural ventilation, one must add in both the disruption and cost of installing a whole house ventilation system which is neither cheap nor easy with floors having to be ripped up for trunking and trunking chases up the walls (assuming more than one storey).

        At a rough estimate, I have calculated that it would cost around £100,000 to convert our small, 3 bedroom, end terrace, solid masonry walled, Victorian house to comply with all this. As the house is worth approximately £300,000 it is simply not a viable proposition.

        This whole endeavour will impact badly on householders who either do comply, or neglect to comply with this ridiculous expectation. Either way, the housing market will be badly disrupted.

        Then there’s the problem of cowboy builders………..

      • Chaswarnertoo permalink
        October 16, 2019 10:38 pm

        Moonbat banged up. Oh frabjous day. Hope he’s uncomfortable.

    • Dave Cowdell permalink
      October 16, 2019 9:31 pm

      Well, we recently moved into a large Welsh house with massive 1 m thick stone walls construction. Radiators and air source heat pumps as the primary source of heating. By the second year of astronomical electricity bills and being freezing cold we then binned it and put in an oil fired system. Maybe I am missing something but is it not an assumption that we climate change we will not need any heating whatsoever in the winter, an extension to the David Viner ” snow is a thing of the past” If we do get a Maunder minimum it will put paid to all this nonsense, ideology has little attraction when you are freezing your nuts off.

      • Kelland Hutchence permalink
        October 17, 2019 8:24 am

        David – Here in France we live in a house some 130 years old, also with walls some 90cm thick. It was a polar hell when we moved in in the month of January some seven years ago. First thing was to install a wood burning stove (most houses in our village use wood for heating as it’s not too costly at around £40/ 44euros per m2 but can be far cheaper if you cut it yourself!). Then I insulated all the exterior walls using a system of rails (available in most DIY stores) supporting 10cm fibre glass sheets and to which plasterboard was attached. Surprisingly, this seems to be unknown in the UK but it is very well known in France and well within the capabilities of most people.. The cost was very reasonable and the effect was to transform the comfort of the house that we can and do live in all year round.

        Regarding heat pumps I assume that most references in this correspondence relates to air sourced pumps. These also seem popular in France but bearing in mind the reduction in efficiency when temperatures drop I’ve often wondered why hardly anybody here seems to make use of their cellar space when available. Almost all houses built in France until quite recently have cellars. I’m no engineer or technician but I discussed this recently with an architect who seemed quite enthusiastic at this possibility. I have two cellars where the temperature is a constant 12C which seems likely to make a suitable and relatively inexpensive compromise between air sourced and ground sourced heat pumps.

      • Graeme No.3 permalink
        October 17, 2019 10:10 am

        Kelland Hutchence:
        Extracting heat from the air in your cellars will result in colder temperatures there, and lower efficiency.
        I suggest that an architect is the last person, Except a member of the CCC, to seek advice from on heating/cooling etc.

        Re stone walls, there was a vogue in the Adelaide Hills for early stone cottages built prior to WW1. A local described them as very cool in summer for the first 3 days of a heat wave, then hell for the next 3 weeks until they cooled down. They were also freezing in winter, which early settlers dealt with by burning tonnes of wood, hence the fire places in every room. Unfortunately the Greenies don’t want trees cut down.

    • David Parker permalink
      October 17, 2019 8:48 am

      My climate observations from a Met. Office site in Oxfordshire, tell me that the 1m soil temperatures are not as stable as those selling ground source heat pumps lead us to believe.
      The lowest temperatures are in Feb/Mar in the order of 5 deg C rising to 17 deg C late Summer.

      • MrGrimNasty permalink
        October 17, 2019 10:36 am

        If insulated buildings in whole towns or cities were heated by ground or air source, would there not be a significant impact on the local ground and air temperatures, and efficiency seriously decline in extended still cold spells?

        Instead of the BBC weather saying 6 or 7C in towns and cities but an air frost in the countryside, they’ll be saying a touch of air frost in the countryside and -5C in towns and cities!

      • David Parker permalink
        October 17, 2019 2:00 pm

        The average difference in max temp between Oxford (Urban) and Me (rural) Jan to Aug this year is 0.52deg C, and min is 0.41 deg C, Oxford higher. Not sure from where the BBC gets its figures.

      • MrGrimNasty permalink
        October 17, 2019 4:25 pm

        The difference between city centers and genuinely rural sites can easily be more than 5C on minimums under favorable conditions on specific days. Obviously it depends on the time of year and the weather conditions etc.

  4. Joe Public permalink
    October 16, 2019 7:04 pm

    Typo alert:

    “The alternative to heat pumps is hydrogen, produced from natural gas via steam reforming. However this is an extremely (INEFFICIENT?) way of replacing gas, both in terms of hydrogen production and converting household appliances and pipes.”

    ———

    The proponents of replacing natural gas with hydrogen mostly fail to realise that one of natural gas’s major benefits is that it can safely & cheaply be stored in quantity.

    In my comment above, I mention we/ve ~33GWh of electricity storage. OFGEM indicates GB Gas Storage Facilities Aug 2018 is ~18,656 GWh; with a daily draw-off capability of 1,518 GWh

    https://www.ofgem.gov.uk/system/files/docs/2019/01/181207_storage_update_website.pdf

    The v/v calorific value of hydrogen is approx 1/3rd that of natural gas, so by changing to hydrogen, we’d lose ~12,400GWh of energy storage.

  5. Immune to propganda permalink
    October 16, 2019 7:19 pm

    If all this is implemented how much will utilities cost? £3,000 per year? Just look at the high price of electricity now.

  6. It doesn't add up... permalink
    October 16, 2019 7:23 pm

    How green will it be anyway, depending on where you live?

    I’ve just encountered this rather interesting site that shows in essence if you want to be sure of having low carbon electricity, live not too far from a nuclear power station:

    https://carbonintensity.org.uk/

    Take a look at the regional section to see just how green or un-green your power is, and how it varies over time.

  7. Stonyground permalink
    October 16, 2019 7:38 pm

    Unless nuclear power is used to generate all the extra electricity, non of this crap will reduce CO2 emissions anyway.

    • Adamsson permalink
      October 16, 2019 8:16 pm

      Nuclear power is not good with variable load, it can do base load really well but for peak load you can’t beat gas. Fortunately we have lots of shale gas we could use.

  8. AZ1971 permalink
    October 16, 2019 8:12 pm

    The UK intends to allocate a set number of therms per person, per day, and per year. No one will be allowed to go over their allotment.

    So as unlikely as that scenario may seem, can anyone explain to me what the UK government push to decarbonise will translate into (and at what expense) if NOT restricting the total number of therms per person?

  9. Dave Ward permalink
    October 16, 2019 8:32 pm

    This CCC inspired lunacy might quickly become academic:

    https://www.thegwpf.com/putin-is-getting-ready-to-put-the-energy-screws-on-green-europe/

  10. Steve permalink
    October 16, 2019 9:24 pm

    Yes.The CCC have been crafty. Of course it will be very expensive and bankrupt the country, but who cares? Just increasing demand to 150GW peak with hydrogen and methane backup plus insulation costs will be enough to make sure that the population can’t afford warm homes. Bring on woolies and freezing condensation.

  11. john cooknell permalink
    October 16, 2019 9:41 pm

    In 1996 I was told by an expert source at the Met Office, that their robust climate models UK will soon have the climate of the South of France.

    In 2006 we had the Stern Review, from a world leading banking economist who we are told can predict the climate and its economic effect, but somehow didn’t predict the world financial collapse caused by lack of governance and oversight by his peers.

    In 2009 things got really serious with official Gov projections of how our climate might warm, or it might get colder and it might get wetter or dryer, but either way it would be severe. Read below and see what has happened, what actually happened is not much change at all.

    https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/69257/pb13274-uk-climate-projections-090617.pdf

    I also read recently on the BBC that a robust study by climate experts shows London will have the same climate as Barcelona in 2050.

    So in my mind we don’t need heating much at all, and have wasted countless millions on insulation.

    • ThinkingScientist permalink
      October 17, 2019 10:44 am

      Great document, I already had the Met Office one from 2009, but this is much better – much more specific and testable. Thanks for the link

    • A C Osborn permalink
      October 17, 2019 10:47 am

      It is now 2050, but back in the 90s it was supposed to be by now.
      Peter F Hamilton’s very good Science Fiction book “Mindstar Rising” written in 1993 was based around Climate Change.
      It was the only drawback to his and many other writers about the future that they the were prepared to push the MM Global Warming meme.

  12. Dave Cowdell permalink
    October 16, 2019 9:46 pm

    Well, we recently moved into a large Welsh house with massive 1 m thick stone walls construction. Radiators and air source heat pumps as the primary source of heating. By the second year of astronomical electricity bills and being freezing cold we then binned it and put in an oil fired system. Maybe I am missing something but is it not an assumption that we climate change we will not need any heating whatsoever in the winter, an extension to the David Viner ” snow is a thing of the past” If we do get a Maunder minimum it will put paid to all this nonsense, ideology has little attraction when you are freezing your nuts off.

  13. HotScot permalink
    October 16, 2019 9:46 pm

    If I may, I’ll put this whole thing in perspective.

    According to the Office for National Statistics, Excess winter deaths in the UK during 2017/2018 were 50,100. The lowest on record was in 2013/14 at 17,310.

    However, the terrifying prospect of people dying during heat waves is quite staggering:

    “According to the NDMA (India’s National Disaster Management Authority) heat waves in India have accounted for over 22,000 deaths since 1992. In 2015, 2,040 Indians died in shocking heatwaves. Recent years have seen declines, to 1,111 in 2016 and 222 in 2017.”

    Yes, that’s two hundred and twenty two!

    That’s strange, we are told a warming planet (which, the IPCC assures us, will occur predominantly in the Northern & Southern hemispheres, in winter, and at night) is a bad planet. Yet in 2017 the UK suffered 50,000 fatalities from cold (nor was it a particularly cold winter) and India, a country with immense poverty, ill equipped to deal with weather extremes, suffers 222 deaths from heat.

    In 27 years India’s total fatalities from heat is only ~5,000 more than the lowest recorded UK deaths from cold in a single year.

    You are of course welcome to verify these figures.

    https://www.ons.gov.uk
    https://ndma.gov.in/en/

    • Chaswarnertoo permalink
      October 16, 2019 10:43 pm

      You and your facts. The Liverpool pathway had to be replaced somehow to kill off the elderly…

  14. October 16, 2019 10:53 pm

    the CCC are projecting peak demand of 150 GW by 2050

    150 GW when the wind’s not blowing? Good luck with that.

    • October 17, 2019 9:45 am

      Or 50 Hinkley Points!

      • Steve permalink
        October 17, 2019 4:50 pm

        50 Hinkleys costing £500 to 1000bn. Much less than the £7tn estimated for Germany’s green decarbonization. As MacKay said ” Why not build nuclear and run them all the time. With gas and other flexible. It’s the 59% from wind that is impossible.

  15. saparonia permalink
    October 16, 2019 11:16 pm

    As we all know that this will result in severe cold, I would like to suggest we all begin to grow trees wherever possible. Even if it’s very cold, too cold to stay inside, you can coppice the trees to sit around a fire outside. Don’t cut them down completely or the following year you will have to sit indoors and huddle together under blankets with your family and pets. (Of course bathing will be out of the question.)

  16. Jongo permalink
    October 17, 2019 12:10 am

    From my experience heat pumps typically provide faster response to heat demand than the electronically controlled gas heater I possess, which for safety reasons must suffer a time lapse of 7 minutes before it can cut in its’ full flame mode. And even in full flame mode the heating effect in the room is still slower in response than friend’s heat pump

  17. Stephen Lord permalink
    October 17, 2019 6:29 am

    Socialism always leads to freezing in the dark.

  18. Graeme No.3 permalink
    October 17, 2019 9:57 am

    The obvious answer is to demolish all homes that would require heating and rebuild them with excellent insulation. Then the air source heat pumps will be all that is required to control the interior climate. Possibly heat banks (surely you have them in the UK?) charged up by electricity during periods when the wind is blowing, or when the 15 to 25 new nuclear stations have spare capacity after charging the EVs that everybody will have.
    Probably cheaper than the current wishful thinking.

    • Michael Adams permalink
      October 17, 2019 5:32 pm

      Why rebuild individual homes when we could all live in large dwellings, some would call the barracks but that so ugly, and heat them much more sustainably than those old fashioned individual ones. To go further we could organise a shift pattern for occupancy which would lessen the footprint even more. Think of the benefits; children would have multiple adults to look after them, you’d only need one kitchen and the old would have someone to talk to all the time. There you have it, Utopia. Just a bit of creative thinking, thats all we need.

    • Gerry, England permalink
      October 18, 2019 1:50 pm

      Oh, dear. Listed buildings. Conservation areas. Heritage areas. Most likely take the rest of the century to get through planning by which time the current outbreak of lunacy will have passed.

  19. Stonyground permalink
    October 17, 2019 10:09 am

    OT but apparently an ER protester who had climbed on top of a tube train with the intention of causing some transport disruption was dragged off it and given a kicking by some angry commuters.

    • Immune to propganda permalink
      October 17, 2019 11:33 am

      Need to do the same to our brain dead politicians.

  20. Michael Adams permalink
    October 17, 2019 11:06 am

    At last some exposure of alternative views on CC and its in MSM

    https://www.telegraph.co.uk/science/2019/10/15/climate-change-fake-news-global-threat-science/

    • Bertie permalink
      October 17, 2019 6:58 pm

      Thanks for bringing this to my attention.

  21. C Lynch permalink
    October 17, 2019 12:24 pm

    Off topic but interesting video on BBC news website today of a extinction rebellion protestor trying to stop a London tube train by standing on the roof. Let’s just say the general public present took him off the roof and made their displeasure known to him in a forthright manner.

    • Michael adams permalink
      October 17, 2019 12:31 pm

      I’m truly surprised the public have taken so long to react like this. I really thought that the porters at Smithfield and Billingsgate would have kicked these people out as soon as they arrived. The world is going soft obviously.

  22. chris edwards permalink
    October 17, 2019 1:37 pm

    What an utter waste of time! first he uses synthasised dats, then in reality there is no way at preset to replace gas, one big drawback to heating with electricity is the losses between beneration and use and electrical heating is a disaster as at varuius times the load will be unsustainable as electric heating draws far more than branded untill the elements warm up. As for using geothermal? I doubt that will work for high density housing as the rocks will cool if you suck too much out too fast, like a drilled well! And all this assumes CO2 causes warming and there isnt anything but alarmism supporting that!

  23. Nancy & John Hultquist permalink
    October 17, 2019 6:51 pm

    There is also the problem that heat pumps cannot provide the sort of instant heat that gas can, so won’t be of much use on cold winter mornings.

    Ours is equipped with electric resistance coil heaters.
    Thus, it is a dual system intended for places that get very cold.
    The cost jumps the moment those heaters kick-in, but the heat is immediate.
    However, this allows for one system, rather than to have a separate, say, gas system.
    Our house, built in 1981, has what is called (wood) stick-frame construction, with batt insulation. Images below, from the web.


    Interior space is [8.89 cm] 3.5 inches (2x4s); need more and they use 2x6s.

    Next one seems to have 8 inches of insulation in the roof.

    • October 17, 2019 7:36 pm

      There’s nothing like a good gas fire to warm up a room in minutes, John

      Unfortunately when we tried to replace ous a few years ago, Elf & Safety man said we were not allowed, as the chimney was too narrow (despite the fact we had had a gas fire for decades!)

      So we had to have electric

      • Gerry, England permalink
        October 18, 2019 1:46 pm

        Install a wood burning stove instead, Paul. I am making good use of my open fire at the moment as the temperature sits on the borderline of turning the CH on.

  24. Philip Foster permalink
    October 17, 2019 9:12 pm

    Heat pumps for about 90% of British housing stock wouldn’t work. On long terraced streets the sounds of hundres of heat pumps would make for very disturbed nights.

    • Gerry, England permalink
      October 18, 2019 1:59 pm

      I don’t see that as a problem as the leftist elite don’t live in terraced streets or anywhere near them.

      • Philip Foster permalink
        October 20, 2019 2:48 pm

        True! I suppose the likely permafrost created by these heat pumps could be exported in some way to Siberia where, apparently, they are in need of it. 🙂

  25. Nancy & John Hultquist permalink
    October 18, 2019 6:00 am

    I still think CO2 is a non-problem, so these top-down regulations just drain wealth from society.
    Nuclear power, in some form, is the only possibility for reducing emissions and continuing to have power.
    And thank the spirits for us living in a region of low cost hydro power;.

    • yonason permalink
      October 18, 2019 3:31 pm

      ”…these top-down regulations just drain wealth from society.”

      That’s their end-game, in a nutshell: enrich themselves and their friends by impoverishing the rest of us.

    • Stuart Brown permalink
      October 18, 2019 7:42 pm

      One week ago China’s Ministry of Ecology and Environment issued the construction license for this:

      One week! If this truly is a picture of what they are doing there they don’t hang about, do they? ( http://www.world-nuclear-news.org/Articles/Construction-starts-on-first-Zhangzhou-unit – in case the picture doesn’t come up)

      France built 58 reactors in 15 years – if we really wanted to decarbonise electricity and heating in the UK, surely you are right. This is the way to do it!

  26. 2hmp permalink
    October 18, 2019 11:22 am

    Lunatic Brighton. In my opinion it starts with the MP and runs right through the councillors down to the lowest council employees. There is no hope for Brighton as a sensible town – which it used to be.

  27. richard verney permalink
    October 18, 2019 1:54 pm

    Heat pumps are expensive.

    They are only efficient when heating low temperature water (eg., around 30 to 35 degC) which is fine with underfloor heating, for modern builds, but no good for old fashioned convective radiators that require water temperature of 65 to 80 degrees C. High temperature air/water heat pumps are available, but at these temperatures the efficiency is not good, usually less than 2.

    Of course, their efficiency depends upon ambient temperatures. Fine when around +8 degC, but not so good when below freezing and especially in the -8 to – 20 degC range which rural Britain sees during winter nights.

    That is the problem with all renewables and so called green solutions, they are at their least efficient precisely when needed most.

    Since heat pumps consume electrity they will become ever more expensive to run as enegry prices rise. The consumer is being sc€wed.

  28. October 18, 2019 3:21 pm

    AFAIK Arctic sea ice was lower in 2012
    But I just came across this graphic
    The interesting thing is the graphic doesn’t appear in the BBCFuture article he is linking to

    Similarly someone else has done another graphic that omits 2012

    • October 18, 2019 5:55 pm

      My feeling is that sure sometimes you can get a date with low ice.
      Then a few weeks later the prevailing winds have come from the other direction and the situation is different.
      Plus sometimes people jump on immediate data which is not fully confirmed and ends up being rolled back a bit later.

  29. Derek Colman permalink
    October 18, 2019 11:59 pm

    I love the bit about heat pumps working less efficiently as the temperature drops. What he means is they stop working when the temperature goes below zero. Heat pumps are a con. They do not work in cold damp conditions, which are normal UK winter conditions. Californians have them to take the chill off below 70°F evenings, which is when they do work, in warm dry air.

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