If you are itching for a new DIY project you could tackle something like solar panels or a wind-generator, but the simplest, cheapest form of renewable energy available to all of us is ‘passive’ solar heating.  This means making maximum use of the sunlight which falls on your home, and works on a few simple principles.

1          Orientation is the the most important factor, and the chapter on light gives many ideas on this which are equally relevant to energy use – see pages 00-00.

2          Have large south-facing windows and smaller ones in north-facing rooms to avoid excessive heat loss there.

3          Leave curtains open throughout the daylight hours, but close them promptly when it gets dark.

4          Don’t use net curtains, especially on south-facing windows.

5          Remember that dark colours absorb sunlight (and heat), while light colours reflect it.

6          Take advantage of the thermal inertia of building materials.  A brick floor will absorb heat from the sun during the day and give it off through the evening, just as a brick garden wall is perfect for espaliered fruit because of the way it retains warmth.

Conservatories are an ideal source of passive solar heat, and can make a substantial contribution towards warming your home, as well as providing an extra room (estate agents also consider them one of the best ways to add value to your property).  If you are a gardener, consider a conservatory as a greenhouse built against the house – much easier to nurture seedlings in February if you don’t have to tramp down a muddy path to get to them. Choose a south- or west-facing site if possible, out of the wind (you can plant windbreak trees or shrubs).  Double glass will help to eliminate any need for heating, and you’ll need blinds and ventilation for hot weather. to an architect able to guide you in more substantial renovation, contact the Ecological Design Association.