Clean fuel
The first thing has to be to use a sustainable fuel to provide the heat which is needed to heat the house. Wood is a clean source of energy, because when it burns it only releases the carbon it absorbed during it’s lifetime, which makes it a nett zero carbon fuel. This can take the form of an attractive wood burning stove in your living room, and if you want this to provide hot water as well it can include a back boiler, or you can go for a fully fledged wood boiler which provides the central heating for your whole house, which loads itself and does not need to be loaded manually.
Wood burning stoves
A wood burning stove is the easiest and simplest way to take advantage of some zero carbon heat for your home. They cost £2-3,000 and are quite a straight forward addition to any home. The only thing which you need to be careful about is the proximity of the flue to windows or rooflights, so that the smoke from the flue does not go straight back into an open window.
These are a very cosy way to provide a boost to your heating system on a cold winter’s night. An issue can be that they churn out too much heat. If the house is otherwise well-insulated, the heating load for the whole house would be around 6kW for a 200m2 house built to current standards. Given that wood burning stoves are generally rated from 5-20kW they can very quickly make a well-insulated house swelteringly hot!
The beauty of them as opposed to open fires is that they burn the wood much more efficiently because they burn the wood at a much higher temperature, and they have a sealed air intake and flue which is closed off from the house so that they do not cause draughts. This makes them much more suitable for modern, air-tight Eco-houses. The downside however is that they need to manually loaded and lit each time they are needed.
Biomass boilers
These are a step up from a wood burner, and generally burn wood pellets, but larger ones can be used which burn wood chip & logs or peat, coke and coal can be burned on multi-fuel burners. They cost a minimum of £10,000, and cost around £100/year more than gas so there are no financial benefits unless your central heating currently runs on oil. Unless of course you have access to your own source of wood!
They are generally much larger than a wood burner, being a couple of feet square and four to five feet tall, with an accompanying pellet store from where the pellets are fed into the burner. They also look pretty functional so are more suitable for the garage than a corner of the living room. They also need a dedicated fuel supply which will take up a few square feet of floor space as well. Either way, due to the sheer quantities of fuel this is not going to be a carefully stacked Scandinavian wood-pile.
Wood pellets are the best fuel because they are designed to burn efficiently with a high surface area, and they are small and move almost like a liquid which makes them suitable for mechanical loaders such as augers. Whilst it cannot be argued that they are cheap to install, they provide a carbon neutral central heating and hot water system, and the RHI of around £1000/year would achieve payback in 12 years.
Passive solar gain
Free energy is always popular, and in the UK any south-facing window will gain more heat from the sun than it loses over the year, meaning that it is free heat for your house. So maximising the number and size of windows on the south side of your house will lower heating bills. They also have the benefit of increasing natural light daylight and views, which doubly improves the atmosphere of a house. Ideally this should be combined with a solid, heat-retaining material on the floor such as a tiled floor or concrete, which ensures that the heat is absorbed and will be emitted after the sun has gone down. The technical term is a material with a high thermal mass, i.e. it heats up and cools down slowly.
Windows should always have blinds and curtains on the inside to reduce heat loss at night and in winter, but these are used in most houses. Also, it is always possible to have too much of a good thing (see below) so you should moderate the amount of glazing, otherwise you can suffer from serious over-heating in the summer. I can also imagine it being a nightmare closing all the blinds in this house at night to prevent heat loss in the winter!
Reducing water consumption
We can all reduce our water consumption by using low flow-rate taps and showers, and WC’s with dual flushes. This is built into the building regulations now, so that they are no longer optional, but a requirement. There are also behavioural changes which we can make to reduce our water consumption. These tips are down to Water-wise.
- Install dual flushes which use 4-6 litres per flush as opposed to the traditional ones 13 litres per flush!
- A cistern displacement device (CDD) is a very simple way to further reduce the water consumption of your flus (by about 1 litre per flush).
- Toilet flushing accounts for 30% of water consumption. Don’t flush cotton wool or make-up tissues down the toilet, but put them in the bin.
- While brushing your teeth only run the tap while washing your brush or mouth! We waste 6 litres per minute with a running tap.
- Low flow or aerated shower heads reduce water consumption while giving the feeling of more water through pressure or air in the water.
- Reduce the length of your showers by using a shower timer!
- Baths typically use 80 litres of water (3 times the amount of showers) so shower more than you bathe!
- Use a full load in your dishwasher and washing machine to maximise the efficiency of every wash.
- Use an aerator on the tap in the kitchen and bathroom sink to reduce the flow rate.
- Put the lid on saucepans while they boil. This will mean that they lose less water through steam and the veggies boil quicker!
Sustainable Urban Drainage Systems (SUDS)
The fact is that annual rainfall is going up every year as a result of global warming. The facts are not in doubt, it is just a case of whether the cause is man-made or natural. In the case of domestic projects your impact will be small, but if you want to do your bit there is always something you can do.
Impermeable surfaces such as paving and tarmac need to be drained, so reducing the extent of the site given over to these reduces rainwater run-off. These surfaces can also drain to a planted area on the site instead of a drain which again prevents the water from going into the drains, as shown in the image below. Permeable paving is also an alternative, as it allows the water to pass through the surface and into the soil below.
A simple soakaway for your home can be made by connecting the rainwater pipes from your house into a gravel strip with a land drain in the bottom. The gravel strips allows the water to sit around for a time before going into the drain which gives a chance for the ground to absorb the water, whilst the drain ensures that the water will always goes down the drain before it has a chance to flood your garden! 
Increasing environmental habitat
The increasing area of our cities which are covered in hard surfaces also reduces the space for animals, birds and insects to feed and live. Most of us would like to see more wildlife in our cities, and so creating spaces for nature can give people a great connection to nature. We can take action on many levels.
- Plant flowers which attract insects, like salvia, redbeckia, lavender and nepeta
- Put out bird feeders and a nesting box.
- Build a wood pile for hibernating hedgehogs
- Dig a pond as a habitat for plants, amphibians and fish, which is probably the best single habitat. Use straw to keep the water clean naturally.
- Ponds should have a shallow area for access by frogs and newts and tall plants for animals to hide in.
- Start a compost heap. It creates natural fertiliser for free and is also a habitat for small creatures.
- Don’t make it too tidy, allow some areas to get overgrown to allow animals to hide.
- Plant a wildflower meadow (a combination of grasses and flowers). These are a great habitat for insects and low maintenance, which are steeply on the decline in the UK, having lost 96% since the 1950’s.
- Create a rock garden, which is a specialised habitat for different plants and animals.
Some cities are taking more serious steps in their architecture. Berlin and Malmo require that 50% of the area of any new development should be a bio-diverse landscape which can be used by birds and insects. As you can imagine this is a pretty challenging requirement, which has led to the green roof-scape of these cities.
