Renewable Energy: 5 Ways You Can Make It On-Site

September 24th, 2007 by Steve Evans

Those approving new property devlopments in many cities have been requiring lower energy consumption performance from our buildings, by increasing insulation requirements, etc. The majority of citizens believe that is for the politicians to set energy economy rules and to force all new property to be built in a manner which will ensure that less fossil fuel energy is used. Nevertheless, to carry on forever, making buildings more efficient makes little sense if the cost rises, or the functionality of the building suffers beyond a certain point. At that point the developer has to be required to start supplying some of the energy the building will need from its own resources, usually these will need to be energy sources available on the site.

A first city to require that its buildings will make some of their own power from now on (2007) is London City, and this has been pushed through by its green mayor, Ken Livingstone.

This article could not be more topical in view of this new energy requirement.
5 technologies are described below which we think could lead the revolution in the cities which would enable at least part of the power of its buildings to be sourced on-site, and reduce the environmental footprint of the big cities.

Solar Panels
Solar cells (Photovoltaics) have been coming down in price for some time, so they have been becoming more frequently seen. We can expect this trend to continue and accelerate.

Wind Energy
Although wind power has taken-off for the large scale wind farms in many nations, with thousands being built, small roof mounted wind generators suitable for buildings, have not been nearly as successful. This may change, although a wind turbine can only create enough power to be worth its cost, if here is enough wind.

Waste
Many buildings now make so much waste that this technology can be a great renewable energy source (for all those organic materials within it which are not fossil fuel derived). Tesco and Sainsbury’s supermarkets in the UK are looking into such equipment, and in particular at Anaerobic Digestion as the preferred technology for doing this, avoiding combustion or incineration which is held in bad regard by the general public.

Heat Exchanging
When you have warm air going outward and you are sucking replacement cold air in it makes sense to pre-warm the cold air by using a radiator so that the warm air can pass its heat energy to the cold air across a heat exchanger. When then heated to room temperature the cold air is warmer than it would have been, and energy saving is the result – or energy regeneration. Is this truly a renewable energy supply? It does use a source of energy available on-site (heat energy), but many already do use this system under the banner of energy efficiency.

In some properties this technique may be applied to the discharge of foul water from baths etc which will be relatively warm and which can be used to pre-heat incoming air or water.

Regenerate Power from the Pressure Reduction Points in the Local Water Distribution System
It seems strange, and is hard to explain, but energy (electric power) can actually be won back from a water mains any distribution system at pressure reduction valve points in the water mains.

There you have it. Five top technologies for renewable energy creation on-site for building designers to use in order to comply with new UK London City development requirements.

Steve Evans is a prolific writer on environmental topics.

Visit his Climate Change Web Site, and don’t forget to also check his blogger blog Anaerobic Digestion Blog.