Friday 17 April 2015

Warm and Green - low carbon energy in and for the countryside

The Warm and Green report published today covers two important aspects of energy and the countryside: low carbon heating in rural areas (especially for people off the gas grid) and the impacts of low carbon energy on rural areas - wind farms, nuclear power stations and so on. I am co-author on the report and doing this research has been quite an eye opener for me. Urban citizens are in the majority but 18% of us live in the countryside - a sizeable minority.

Mark and Diane's cottage in Derbyshire,
now with biomass boiler.
As background to our research we found that rural homes are by and large older, larger and need more energy to heat than urban homes. Our modelling found that rural homes generate 25% more carbon emissions for heating than urban homes, on average. Also about a third of rural homes are off the gas grid and tend to use LPG (gas in cylinders), oil or electricity for heating. These fuels are more expensive than gas from the grid, adding to the cost of heating for many rural homes.

We interviewed a selection of householders with interesting stories to tell and we also talked to people who ran community buildings. Unfortunately we could only feature a few in detail in the report. However the four cases we chose highlight a range of issues (all names have been changed):

  1. Oil central heating conversion to biomass
    Mark and Diane live in a beautiful cottage in Derbyshire. They love the place dearly but the price of oil was getting ridiculous and they could no longer afford to keep comfortably warm. They ended up with a new biomass boiler and they are so delighted with it they recommend it to all their friends. It is pretty much a direct replacement for the old oil boiler - running on a programmed timer and heating a wet radiator system just as before. This solution works well for them, is low carbon and affordable - but if everyone went down this path we would not have enough land to grow the biomass.
  2. Internal insulation under protest
    Mary has recently moved into a new home where she expects to live out her retirement. Getting the place ready involved extensive refurbishment and building regulations stipulated that she must install internal insulation at the same time. She really didn't want to do this because, she said, 'space is more important to me than energy saving'. Is this unreasonable interference? It is impossible to know the resulting savings because we can only guess what her bills would have been like otherwise.
  3. New build to Passivhaus standard - 85% fuel savings
    Hastoe Housing Association were the first in the UK to build new homes to the Passivhaus standard, so called because Passivhaus homes run most of the time with no heating at all. They are so well insulated and so airtight they are comfortably warm just from the 'passive gains' from appliances we use in the home, solar gains through windows and our own body heat. In the first full year the residents used 85% less gas than they did in their previous homes. As one family said, 'it means we can spend more money on presents for the children'. The Hastoe homes cost 12% more to build than traditional techniques but it is always expensive being a pioneer. Some reports suggest Passivhaus can now be as cheap or even cheaper to build than standard construction [2]. So why aren't all new homes Passivhaus or similar?
  4. Combs Village hall - a retired engineer applies his skills.
    After the hall was leased to the local primary school the heating bills rocketed, the rent did not cover the costs and something had to be done. However, the trust chairman, a retired engineer, was willing and able to take up the challenge. It was a long and complex project with many small steps on the way, but ultimately the night storage heaters and infra red panels were replaced by air to air heat pumps, a larger hot water tank was installed with solar panels to heat it and some top-up insulation added. Also, and very importantly, the heating controls were restricted so that building users could not turn the thermostat up high or leave the heating on all night. Result: the bills are down by half. Plus Mike has applied what he learned to advise other local residents, encouraging them to take up insulation grants that were available at the time. Some were so impressed with the air to air heat pumps in the hall they installed them in their homes too (though these are not supported by the RHI). If only there were more like Mike in the world - but we can't always rely on volunteer experts to give impartial advice.
We asked our interviewees where they went for advice and how they chose their installers, and got a wide range of answers. Advice from the internet was not always easy to follow or consistent, but then neither was advice from 'expert' salesmen. Some people hired local contractors they had worked with before, others found specialist installers were cheaper, even though they were based hundreds of miles distant.

The second part of the report is to do with modelling at a national level (not just the rural homes) how much we can expect to reduce our energy needs with retrofit solutions and the gap between what that achieves and where we need to be to hit our carbon targets. That in turn tells us how much low carbon energy we need, from which we can determine the likely landscape impacts. If we got all that heat from biomass it would mean a third of England's land area taken up with woody crops.

This is only one projection, of course, and a lot depends on the level of effort we put in to energy efficiency as well as energy generation. However, it certainly helps to be reminded where we should be aiming our sights. In my own case, a comprehensive but fairly conventional retrofit means we have reduced our energy use by about half (see A retrofit experience) - but is that enough?

[1] Warm and Green (CPRE) April 2015
[2] Low energy low cost, Passivhaus on a budget (article for Passiv House Plus) March 2014

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