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Elevated levels of CO₂:

China and the USA are the largest emitters of CO₂.

CO₂ emissions into the atmosphere are increasing at a rapid and accelerating rate and are now at their highest level in 15 million years (or even in 66 mln years)

Neither country has committed to a reduction of their total emissions by 2020.

from fossil fuels:

Fossil fuel combustion from various industrial processes accounted for about 15% of total U.S. CO₂ emissions.

Carbon dioxide (CO₂) is the primary greenhouse gas emitted through human activities. The main human activity that emits CO₂ is the combustion of fossil fuels (coal, natural gas, and oil) for energy and transportation, although certain industrial processes and land-use changes also emit CO₂.

Carbon dioxide emissions in the United States increased by about 7% between 1990 and 2013.

The combustion of fossil fuels to generate electricity is the largest single source of CO₂ emissions in the nation, accounting for about 37% of total U.S. CO₂ emissions.

To produce a given amount of electricity, burning coal will produce more CO₂ than oil or natural gas.

The combustion of fossil fuels such as gasoline and diesel to transport people and goods is the second largest source of CO₂ emissions, accounting for about 31% of total U.S. CO₂ emissions

The most effective way to reduce carbon dioxide (CO₂) emissions is to reduce fossil fuel consumption. Reducing personal energy use and using more energy from renewable sources are ways to reduce carbon emissions and greenhouse effects.


versus solar enegry:

Solar radiation reaches a unit of space near the Earth’s orbit at a rate of 1,366 W/m² (Watt per square metre), as measured upon a surface normal (at a right angle) to the Sun. This number is the "solar constant". Of this energy, about 19% is absorbed by the atmosphere, and clouds reflect a further 35% of the total solar energy. Therefore solar energy received a sea level is much less. Its peak power is generally accepted to be 1,020 W/m².

Solar cells have about a 15% efficiency rate in converting that energy. Therefore solar panels deliver only 19 to 56 W/m² or 0.45-1.35 kWh/m²/day of that average power. But that does not make solar energy inefficient!

In the Mojave Desert in North America that houses the world's largest solar power plant. It covers 1000 acres (4 km²) of solar reflectors.

In the late 15th century Leonardo Da Vinci already conceived of an industrial use of solar power by employing concave mirrors to heat water.

In North America for example the average power of the solar radiation is roughly between 125 and 375 W/m², that is between 3 and 9 kWh per m² per day.

The energy output of a 1 KW solar energy unit is roughly equivalent to the burning of 170 pounds of coal and 300 pounds of carbon dioxide being released into the atmosphere.

In recent years manufacturing costs of photovoltaic cells has dropped by 3-5% per year while government subsidies have increased.

There are around 2 billion world citizens without any electricity at all. To them the facts about solar energy are that they cannot flick a switch to bring it on and are often steeped in poverty.