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The theory of global warming is nothing new. The Nobel Prize-winning chemist Svante Arrhenius first proposed the idea of global warming in 1896. Carbon dioxide, he knew, traps heat in the Earth's atmosphere. He also knew that burning coal and oil releases carbon dioxide (CO2).

Winds are caused by the interaction of the uneven heating of the atmosphere with the uneven surface of the earth, and the earth’s rotation

This ultimately reduces the cost these power plants can sell their electricity

By the time it reaches Earth's surface, the energy in sunlight has fallen to about 1,000 watts per square meter at noon on a cloudless day. Averaged over the entire surface of the planet, 24 hours per day for a year, each square meter collects the approximate energy equivalent of almost a barrel of oil each year, or 4.2 kilowatt-hours of energy every day. Deserts, with very dry air and little cloud cover, receive the most sun—more than six kilowatt-hours per day per square meter. Northern climates, such as Boston, get closer to 3.6 kilowatt-hours. Sunlight varies by season as well, with some areas receiving very little sunshine in the winter. Seattle in December, for example, gets only about 0.7 kilowatt-hours per day. It should also be noted that these figures represent the maximum available solar energy that can be captured and used, but solar collectors capture only a portion of this, depending on their efficiency. For example, a one square meter solar electric panel with an efficiency of 15 percent would produce about one kilowatt-hour of electricity per day in Arizona.

Hydrogen as the Main Fuel of the Future Over the last decades hydrogen, (H2) has gained more and more attention as an environmentally friendly fuel and storage medium. Combustion of pure hydrogen produces only water as exhaust. Hydrocarbon and carbon oxide emissions can only come from motor oil in the combustion chamber. Nitrous oxide emissions result from the nitrogen content in the air and increase exponentially with the combustion temperature. By using H2 in fuel cells, practically no pollution occurs. In this respect, hydrogen offers emission levels that are much lower than existing and future standards.

Hydrogen is the most common of all elements in the universe.

The desire for a long-term transition to a hydrogen society is mainly based on the need to reduce polluting and climate-affecting emissions and the concern about depletion of fossil fuel resources. Today about 90 % of the world's energy consumption is covered by fossil fuels, and most of this comes from a limited number of regions in the world. Even if hydrogen will be used on a large scale in the future, there is still a need for an energy source to produce it. Renewable energy technology such as hydro electricity, wind, wave and solar power are in principle available, but are not yet mature for mass production and/or fully developed. 

Energy from the Sun The sun has produced energy for billions of years.  Solar energy is the sun’s rays (solar radiation) that reach the Earth. This energy can be converted into other forms of energy, such as heat and electricity.

Photovoltaic (PV devices) or “solar cells” change sunlight directly into electricity. Individual PV cells are grouped into panels and arrays of panels that can be used in a wide range of applications ranging from single small cells that charge calculator and watch batteries, to systems that power single homes, to large power plants covering many acres.

Solar energy systems do not produce air pollutants or carbon-dioxide

What is wave energy? Waves are generated by the passage of wind across the surface of the sea.  Energy is transferred from the wind to the waves.  Waves travel vast distances across the ocean and at great speed and the energy is concentrated near the water surface.  The energy within a wave is proportional to the square of the wave height.  Therefore a two-meter high wave has four times the power of a one-meter high wave. The longer and stronger the wind blows over the surface of the sea, the higher, longer, faster and more powerful the sea is.

Although wave energy is a form of concentrated wind energy, as it has often travelled over large distances it is regularly out of phase with the local wind conditions.  Wave energy can therefore help to balance output variability from other renewable sources and maximise the efficient use of the electricity networks.   Wave energy is also more predictable than many other forms of renewable energy, such as wind or solar, and can be forecast accurately up to five days in advance.

Wave energy is clean and renewable!  It is one of the last renewable energy forms which mankind has yet to harness, and its potential is huge.

Like many renewable resources, geothermal resources need relatively high initial investments to access the heat, hot water and steam. But the geothermal "fuel" cost is predictable and stable. Fossil fuel supplies will increase in cost as reserves are exhausted. Fossil fuel supplies can be interrupted political disputes abroad. Renewable geothermal energy is a better long term investment.

Examples are the huge costs of global climate change; the health effects from ground level pollution of the air; future effects of pollution of water and land; military expenditures to protect petroleum sources and supply routes; and costs of safely storing radioactive waste for generations. Geothermal energy can already compete with the direct costs of conventional fuels in some locations and is a clean, indigenous, renewable resource without hidden external costs.

Method Cents/kW-h Limitations and Externalities WindCurrently supplies approximately 1.4% of the global electricity demand. Wind is considered to be about 30% reliable. 4.0 - 6.0 Cents/kW-h Wind is currently the only cost-effective alternative energy method, but has a number of problems. Wind farms are highly subject to lightning strikes, have high mechanical fatigue failure, are limited in size by hub stress, do not function well, if at all, under conditions of heavy rain, icing conditions or very cold climates, and are noisy and cannot be insulated for sound reduction due to their size and subsequent loss of wind velocity and power. GeothermalCurrently supplies approximately 0.23% of the global electricity demand. Geothermal is considered 90-95% reliable. 4.5 - 30 Cents/kW-h New low temperature conversion of heat to electricity is likely to make geothermal substantially more plausible (more shallow drilling possible) and less expensive. Generally, the bigger the plant, the less the cost and cost also depends upon the depth to be drilled and the temperature at the depth. The higher the temperature, the lower the cost per kwh. Cost may also be affect by where the drilling is to take place as concerns distance from the grid and another factor may be the permeability of the rock. HydroCurrently supplies around 19.9% of the global electricity demand. Hydro is considered to be 60% reliable. 5.1 - 11.3 Cents/kW-h Hydro is currently the only source of renewable energy making substantive contributions to global energy demand. Hydro plants, however, can (obviously) only be built in a limited number of places, and can significantly damage aquatic ecosystems. SolarCurrently supplies approximately 0.8% of the global electricity demand. 15 - 30 Cents/kW-h Solar power has been expensive, but soon is expected to drop to as low as 3.5 cents/kW-h. Once the silicon shortage is remedied through alternative materials, a solar energy revolution is expected.

Tide 2 - 5 Cents/kW-h Blue Energy's tidal fence, engineered and ready for implementation, would provide a land bridge (road) while also generating electricity. Environmental impact is low. Tides are highly predictable.

Method Cents/kW-h Limitations and Externalities GasCurrently supplies around 15% of the global electricity demand. 3.9 - 4.4 Cents/kW-h Gas-fired plants and generally quicker and less expensive to build than coal or nuclear, but a relatively high percentage of the cost/KWh is derived from the cost of the fuel. Due to the current (and projected future) upwards trend in gas prices, there is uncertainty around the cost / KWh over the lifetime of plants. Gas burns more cleanly than coal, but the gas itself (largely methane) is a potent greenhouse gas. Some energy conversions to calculate your cost of natural gas per kwh. 100 cubic feet (CCF)~ 1 Therm = 100,000 btu ~ 29.3 kwh. CoalCurrently supplies around 38% of the global electricity demand. 4.8 - 5.5 Cents/kW-h Increasingly difficult to build new coal plants in the developed world, due to environmental requirements governing the plants. Growing concern about coal fired plants in the developing world (China, for instance, imposes less environmental overhead, and has large supplies of high sulphur content coal). The supply of coal is plentiful, but the coal generation method is perceived to make a larger contribution to air pollution than the rest of the methods combined.

"As the sun warms the Earth's surface, the atmosphere warms too. Some parts of the Earth receive direct rays from the sun all year and are always warm. Other places receive indirect rays, so the climate is colder. Warm air, which weighs less than cold air, rises. Then cool air moves in and replaces the rising warm air. This movement of air is what makes the wind blow."

Geothermal power plants, which use heat from deep inside the Earth to generate steam to make electricity. Geothermal heat pumps, which tap into heat close to the Earth's surface to heat water or provide heat for buildings.

At a geothermal power plant, wells are drilled 1 or 2 miles deep into the Earth to pump steam or hot water to the surface.

hot springs, geysers, or volcanic activity, because these are places where the Earth is particularly hot just below the surface.

When we get electricity from renewable energy sources like wind and solar power, we avoid the carbon dioxide emissions that would have come from burning fossil fuels like coal, oil, or natural gas.

The combined health, environmental, and climate benefits of a solar panel in New Jersey are fifteen times greater than those associated with one in Arizona, and a wind turbine in West Virginia displaces twice as much carbon dioxide as the same turbine would in California.