For more than a century, we have relied on oil to fuel our cars. But did you know that the world’s oil is close to drying up because it is a non-renewable resource? Well that may not happen tomorrow or next year but we are getting closer because of the demand in the world market. Why wait for that day when we can rely on a green energy source like water to power our cars.

Water can power a car? If you think that’s impossible, well it is already here but is not yet being made on a commercial scale.

The German automobile BMW company produced the world’s first ever hydrogen powered car in 2006. While only 100 of these units were produced initially there are plans to continue the development to make it more readily available, you can imagine the oil savings if more of these vehicles are on the road.

The initial model namely the BMW Hydrogen 7 uses the body of the 760i model. Once you pop the hood, you will notice that the engine is different since it is dual fuel and uses gas and hydrogen.

This means we have not yet totally abandoned our dependence on gas. Given more time and money, the current 4.7 miles per pound of hydrogen used could hit double digits in the future.

The biggest challenge to using water as a green energy source, as opposed to oil, in vehicles is the current engine technology. While there are cars around like the Prius which runs on electricity and gas thanks to fuel cell technology, the hydrogen combustion is less than 10 years old so you could say we are only seeing the tip of the iceberg.

With the success of the BMW H7, the company came out with a new car that is also partly powered by water known as the H2R. While we cannot yet put our garden hose into the fuselage to fill it up, this vehicle uses liquid nitrogen as a fuel.

Tests on this vehicle have shown it can achieve 285hp and reach a top cruising speed of 185.5 miles per hour. It can also accelerate from 0 to 60 miles per hour under 6 seconds.

But why use water? It is because hydrogen combustion is clean so it does not emit harmful gases into the atmosphere unlike cars that run on petrol or diesel that emit carbon monoxide. Studies have shown that it also weighs less than hydrocarbon-based fuels and burns faster than conventional gasoline.

So when can you expect to buy a car that uses water as a green energy source? Hopefully in the next 10 to 20 years. It is really up to the automakers because all we can do is wait until better engine technology is available.

Right now, the best option we have is electric cars. Since their introduction in 1999, more people are using them because the running costs are far lower (though the initial purchase price is still far higher) and the impact on the environment is far less than conventional automotive power plants.

The next big technology that looks likely to be developed is in the field of solar powered cars. Up to now the only ones that have been seem have been prototypes used for development purposes. But with far more photovoltaic cells becoming available it may not be too many years in the future before a commercially viable solar powered car is launched.

Why is hydropower a green energy source? It is because we are able to harness electrical power by converting water into electricity.

The use of hydroelectric power or even hydroelectricity dates back to Ancient Greece and China when they installed waterwheels in rapidly flowing rivers to turn millstones and other equipment. Years later, this was used in the New World which is now known as North America to power saws and other equipment.

But the hydroelectric plants of today still use the same basic principles as the historical waterwheel with some variations. The difference is that we use the force of the power to push the turbine which in turn powers a generator thus generating electricity.

To make sure that there is a steady flow of power being produced, a dam has to be built to retain the water. If there is a need for more power, the gates of the dam are opened so water can be released. During non-peak, the gates are closed. To ensure there is water at all times, some dams have a recovery and pumping systems to the water released can be used again.

There are issues with the use of hydroelectricity. Some claim that it poses a problem for fish and aquatic plants on both sides of the dam. Because the flow of water has been altered, the nutrient rich silt which helps crops grow could be affected which is exactly what happened when the Aswan Dam was completed in Egypt.

But there are ways to fix that and the bigger picture is that power produced from hydroelectric plants do not generate any emissions or waste which happens to be much better than operating a coal-fired power plant.

There is another way to generate hydropower and you get this form the sea. This is also known as wave power or wave energy which uses changes in the air levels of sealed chambers to power turbines. When a wave rises into the chamber, the rise water pushes the air out which then turns a generator.

Once the wave goes down, air flows into the turbine and back into the chamber through doors that will close.

These chambers remain afloat on the ocean and how much power it produces varies. A lot of these are used on the western coasts of Scotland, northern Canada, southern Africa, Australia, and the northwestern coasts of the United States. These systems are usually small and can power a warning buoy or a small light house.

There is also tidal energy. The difference with wave energy is that when the tide approaches, the water is trapped in reservoirs behind dams. When the tide drops, the water behind the dam is released thus producing power similar to a hydroelectric power plant.

This can only work if you have tides that are at least 16 feet and since there are only a few places in the planet that can do that.

Lastly, you have ocean thermal energy. Here, you get power based on the different temperatures in the water. For this to work, you need at least 38 degrees Fahrenheit difference between the warmer surface water and the colder deep ocean water. Still in the trial stage, it is used Japan and Hawaii.

Hydropower is a green energy source. It is safe to use and what is even better is that it is renewable.

Everybody wants green energy. Being able to get the power we need without damaging the environment is an obvious goal – but what’s the best way to achieve it? Should we be opting for wind farms, hydroelectricity, or solar energy as alternative power?

Renewable Energy is energy created from resources that are regenerative – or renewable – meaning they cannot be depleted. These resources are safe for our environment and produce energy without the harmful pollutants and emissions associated with fossil-fuels.

Wind farms often receive a bad press, especially when they’re situated near homes or in popular hiking areas. They can make a lot of noise and because they have to be placed on skylines for maximum efficiency they often spoil views. Offshore wind farms are less problematic in this way and can take advantage of fierce sea winds, increasing their output, but they rely on a nation having a lot of suitable coastline.

While the Netherlands does very well with its wind farms, the US is, considering the comparative size of its population, at a distinct disadvantage. For the home-owner, small wind-powered generators are available, but they’re not very efficient and often result in complaints from neighbors.

Hydroelectricity is a much more effective way of generating power, using the natural energy of rivers or tidal forces. However, there are a limited number of suitable locations for hydroelectric generators, and often these are in areas which already provide fertile farmland, so a lot of people have to be displaced and lose their land in order for them to be built. They can also have a damaging impact on local wildlife.

Of these three major options, only solar energy as alternative power passes the test of being truly non-polluting, practical and easy to access. Modern solar panels can still function effectively even in areas where it’s frequently cloudy. They don’t get in anyone’s way and, once installed, they require very little maintenance. For these reasons, the greenest way to generate the power we need is by harnessing the power of the sun.