If you plan to build a house you should really ask the architects to plan the new building in such a manner that the energy loss in the winter or during cold days is minimal. Think that circa half of the heat loss happens through walls and poorly insulated window frames and an important percentage through ventilation systems. The orientation of the new building is also important: north south, with large windows on the south and smaller on the north (if possible no windows at all on the north). And don't overlook proper insulation. If this is done right from the first phase of the building process, you'll not have energy loss problems later or other problems such as mildew.

However, if you already live in a poorly insulated building, don't despair! There are some simply ways of improving energy efficiency and they don't imply huge expenses. Start by replacing your windows with low-emission glass windows (or just change the glass). Low-E is a new technology based on a special metallic coating that is transparent to the solar spectrum and reflective of IR radiation that lowers the amount of energy loss.

If your walls aren't insulated, depending on their construction, there are three insulation types you should consider to reduce energy loss: cavity, internal and external. Insulation will reduce heat loss and certainly the energy bills. And don't forget installing draught excluders on your doors and windows.

Solar systems - like solar hot water panels - could provide more than 50% of your annual hot water needs. There are more and more homeowners installing solar panels on their houses. Such systems not only produce warm water practically for free, but also increase considerably the value of a building. Some homeowners even use rainwater systems to reduce water costs and help protect the environment. The rainwater is collected in special containers and can be used as drinking water after it is filtered and purified. Such rain harvesting systems are not always low-priced, but the savings they provide make the price worthwhile; in time you'll cover the cost of your purchase.

If you have a boiler older than 10-15 years, you should replace it and purchase a high efficiency condensing boiler. This might save you about 1/3 on your heating bills because they convert more than 88% of the fuel into heat, while conventional boilers convert about 70-75%. If you cannot afford a new boiler you might consider insulating your hot water tank and the water pipes to reduce heat loss.