Green energy resources are so-called because they are virtually unlimited, providing power for as long into the future as the technology exists to take advantage of them. They are the future of energy production for the human race, and will need to be adopted because the supply of fossil fuels will run out eventually. The key is to make sure that we make the changeover while we still have enough fossil fuels left to create the technology we need to take advantage of the renewable resources, and while there is time to make that technology efficient.
There are many different technologies which can be used to generate power indefinitely. Some of the best known are solar power, wind power, and geothermal energy. Solar power is the best known of all, and has the capability of solving the world energy crisis all by itself. Even though there are some parts of the world with extremely cold climates and little sunshine, there is still a potential for using solar power to generate a part of the energy needs of those regions. In countries with hot climates and extended sunshine hours, the potential exists for solar power alone to meet the energy requirement.
Some countries will benefit from using a mixed approach, combining solar power with wind or geothermal power depending on the climate and terrain. Most of northern Europe has a cold climate, but the countries typically have an extensive coastline with high winds. Wind power is a natural resource for such areas, and when it can be placed offshore the potential is even greater. The technology is still far from being fully developed, and there will need to be extensive onshore development before the turbines are ready to be taken offshore in any serious way.
Some localized areas will have natural features which make them especially suited to other forms of renewable energy. A good example is land which is next to a river with strong currents, a river which can be controlled and used to turn a water turbine and to generate electricity. This type of water installation is not cheap to erect, but it is relatively easy to maintain, and it is also a cost effective way to generate electricity for a local community. It is possible for communities to achieve a degree of independence from the grid network, but connections will still need to be maintained for security reasons.
Although maintenance of this national infrastructure is obviously important, it is likely that the future will see a move towards sustainable energy for smaller units. This includes the smallest unit of all, the individual household. At the moment, it is not possible for a household to use purely green resources to provide all of its energy needs, at least not without significant investment in low energy appliances. It is possible for a portion of domestic supply to be produced this way, and even for some electricity to be sold back to the grid. As the efficiency of photovoltaic panels improves, it will be possible for a greater proportion of energy to be created on site.
The use of green energy resources remains controversial, as it needs to be so heavily subsidized. With the downturn in the world economy, it is obvious that many projects are having to be abandoned. The hope is, of course, that the technology will become economically viable at some point in the future. This is likely to happen when photovoltaic panels are able to capture more of the sunlight than the present models, and advances are already being made in that direction. It is a major step forward for green energy resources.