At various points in the Scottish design festival over the past few days I've learnt a few interesting things about building ecological houses. My main learnings:
- I already know that big south-facing (double-glazed) windows are a very good idea, trapping heat and light from the sun (so it cuts your bills as well as saving the earth). I saw various designs which add to this by putting stone or concrete walls/floors in those south-facing rooms: these serve as heat-sinks or storage heaters and absorb heat, warming the house at night (and cooling it in the day) to cut your heating bills even further.
- A low-tech but important measure is to protect a home from cooling winds, by putting obstacles between the wind and the house. These could be a garage, a conservatory, a bike alcove, or trees/bushes.
- LED lighting is even more efficient than modern energy-saving bulbs, and has been improving a lot in recent years. (For example, they're very commonly used in vehicle indicator lights now.) Still, I don't find the colour of the white LED lights very "warm" - it does seem kind of stark and clinical. Could filters or other tricks help?
- I had thought that burning wood for heating was a bad idea (all the CO2 produced), but apparently not. Wood is renewable in a way that coal and gas aren't, and although electricity is extremely convenient it is not always the most efficient way to heat things (compare gas hob cookers against electric ones, for example). It's also probably less eco-friendly, depending partly on how the electricity is produced, but also because of the inefficiencies of conversion/transmission involved in electric heating. Various "eco buildings" we visited use wood fires or more sophisticated woodchip burning systems. For domestic uses, systems that burn wood pellets are the thing to go for. You can get very compact heater/boiler systems and because the pellets are compressed they don't take too much room to store.