Solar Energy Introduction
New developments in solar technologies are now being fuelled by a number of factors such as the increased numbers of low voltage, energy efficient gadgets, mobile PCs and communicators as well as the rising demand for solar powered hot water heating. The low maintenance of many solar technologies lends itself to remote applications. In less economically developed nations low tech devices such as solar ovens are much in demand. On the industrial scale there are a growing number of large grid tied solar arrays and the prospect of the world’s first giant solar tower.
Although traditionally expensive, the hard wearing, zero maintenance nature of PV already powers the global satellite communication infrastructure, navigation lighting buoys and weather data logging instrumentation. Economies of scale promise to bring such technology within the pocket of the individual consumer and encourage the integration of PV systems into buildings.
The simple fact that none of the PV manufacturing processes have yet delivered energy conversion rates much beyond 20%, whilst solar thermal technologies can offer 8O% and beyond continues to encourage the deployment of solar thermal systems.
Solar Energy is used to provide buildings with space heating and water heating. Roof mounted solar water heaters are proving valuable additions to buildings. Certain countries are experiencing very high consumer uptake levels- Israel now has solar hot water heaters on 50% of its buildings. These figures indicate how swiftly such technologies can capture an aware and committed market.
Using simple technology, solar ovens can be built to either cook small amounts quickly or larger amounts more slowly. In arid zones which tend to be sunny, such technologies can help conserve precious remnants of woodland that are being destroyed due to fuel wood scavenging for cooking.
Solar Thermal Electricity
Using solar concentrators, high temperatures can be gained which can be converted into electricity via an increasing range of devices such as heat exchangers, steam turbines and sterling engines.
Additional to the better known solar energy technologies an interesting concept known as a Solar Towers is making an entry into the Renewable Energy world.
Hybrid Solar Lighting
A new emerging concept known as hybrid solar lighting may offer an effective way of routing daylight deep into buildings. Using parabolic reflectors, direct sunlight can be concentrated on a smaller mirror which after removing most of the Infra red component (which can be extracted as electricity), reflects a very focused beam of visible light on to the end of a optical fibre bundle. This cooled beam of concentrated full spectrum natural light can then be routed into the interior of buildings for illumination. The hybrid design allows this additional lighting source to be mixed with back up lighting to create a dynamic system that always maximises the amount of natural light fed into the building.