The auto industry is under massive pressure to cut down on carbon emissions by finding alternative fuels for cars. Let's explore those alternative fuels!
Natural Gas for use in automobiles is very popular in America because more than 80% of the natural gas used in U.S.A is produced in the country making it a lot cheaper than conventional petroleum .
It is used either as Compressed Natural Gas (CNG) or Liquefied Natural Gas (LNG) when running motor vehicles.
Moreover, it promises a reduction in smog of between 60 & 90%  and a reduction of carbon emissions of between 30 & 40% .
However, certain modifications need to be made on the cars and their tanks in order to use the fuel .
Ethanol is a biofuel used to run engines that originally used petrol. There are a few modifications done to the vehicle so that it can run efficiently on Ethanol.
A vehicle with these modifications is classified as an FFV or a Flexible Fuel Vehicle .
Brazil is one of the countries that have embraced this technology into their system becoming the second largest producer of ethanol in the world by producing sugarcane based ethanol .
Through these developments, Brazil has been able to thrive in the Flex Fuel Vehicle market enabling them to manufacture cars like the Brazilian Fiat 147 , the first modern automobile that could run on pure-unblended ethanol followed by Volkswagens, Chevrolets, Toyotas and Nissans just to name a few .
Like ethanol, biodiesel is a renewable alternative fuel for cars. This is because it is made from plants.
Biodiesel does not require fermentation like ethanol; it is made by a process called trans-esterfication  which converts vegetable fat into an oil that can be used to run ordinary diesel engines without any modifications necessary.
Some vehicle manufacturers are wary of warrantying their vehicles against the use of high blends of biodiesel above 5%  because there are concerns of the fuel’s impact on the engine .
To counter the claims of environmentalists who are against the use of food crops for biofuel production  and the use of arable land to grow energy crops rather than food crops , researchers have developed a biofuel from plant waste .
It is estimated that about 20% of the watermelons produced in a farm cannot be sold for human consumption and go to waste ; these can be converted into a biofuel because watermelon juice contains a considerable percentage of amino acids and directly fermentable sugars, which are essential for the production of bio-ethanol .
Biofuel generated from plant wastes was used to power the limousines that transported certain heads of state to the Copenhagen Climate Summit in 2009 .
A lot of research has gone into the improvement of biofuel production and application. One such study has led a firm in Preston called Ecotec to produce a biofuel from the waste collected during the processing of chocolate. The waste chocolate is turned into bio-ethanol then mixed with vegetable oil to run a special car they have branded the ‘Bio-Truck’ .
LPG is made up of a mixture of hydrocarbon gases of which propane is in the largest percentage thus the fuel is often called Propane .
LPG is produced from the processing of natural gas and the refining of petroleum. It can also be used domestically for cooking and boiling water.
The propane is gaseous at room temperature but is liquefied when compressed to about 200 psi for storage in a special gas cylinder. The use of LPG to run automobiles is more popular in Europe that the US and makes up more than 10% of the motor fuel used in Netherlands .
Last but not least we have electricity. Electricity is the modern man’s fire and every technology is inclined to maximize the use of this energy source.
The use of electricity as an alternative fuel has birthed vehicles of all shapes and sizes, from SUVs to Sports cars  .
The use of electricity has also led to the development of hybrid cars that run on fossil fuels and electricity alternatively - depending on the vehicle’s settings - such as the Toyota Prius and Honda Insight .
However, like all mobile electric appliances, these vehicles contain batteries that need to be recharged.
They have an advantage over hydrogen cars because they do not need several filling stations because electricity sources are widespread, but it is still a tedious time consuming process.
The tesla motor company, which has specialized in the electric car production, has one of its best cars running for only 160 miles per charge .
Electric cars are still not very popular because the automobile industry has not embraced the technology fully thus the cars are still rare .
They do have several advantages over gasoline cars in that they do not produce any tail pipe emissions and cost about 2 US cents per mile compared to gasoline’s 12 US cents .
Furthermore they do not require any of the services that a gasoline car needs such as oil changes and emission checks .
In Hydrogen Fuel Cell Vehicles, Hydrogen is used in a totally different way; Hydrogen is stored on board and mixed with oxygen in the air to generate electricity via the fuel cell stack to power an electric motor that drives the vehicle .
Hydrogen, as an alternative fuel for cars, is deployed either for use in Fuel Cell Vehicles (FCVs) or Internal Combustion Engines (ICEs).
Hydrogen is considered the clean energy of the future burning in an internal combustion engine to produce heat and water vapor as well as other oxides of nitrogen which are also carbon neutral .
There are however, several challenges to overcome before hydrogen for automobiles can be used commercially.
The Fuel Cell Vehicles as well as the Hydrogen Fuel is currently very expensive to produce and the technology of production is not widespread thus ordinary consumers cannot afford to use them .
Furthermore, hydrogen contains less energy per unit volume compared to conventional automobile fuel; therefore, filling stations need to be established at high frequencies in the country of use before the technology can be commercially viable .
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 U.S. Department of Energy – Fuel Economy; Ethanol: http://www.fueleconomy.gov/feg/ethanol.shtml
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 U.S. Department of Energy – Fuel Economy; Biodiesel: http://www.fueleconomy.gov/feg/biodiesel.shtml
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 U.S. Department of Energy – Fuel Economy; Hydrogen: http://www.fueleconomy.gov/feg/hydrogen.shtml
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The sun provides us with unlimited energy, just waiting to be harnessed. Below we'll walk through two fantastic diy solar methods.
Using solar energy for domestic water heating is one of the most cost-effective ways to reduce your power bill and the carbon footprint of a household.
Either evacuated tubes or flat plate collectors can be used for diy solar hot water. A conventional boiler or immersion heater can be used to produce hot water for those occasions when the sun does not oblige, which is often necessary for night-heating or in countries where sun exposure is weak in winter .
The type of system chosen depends firstly on whether freezing is likely to occur. In climates where freezing is not a problem, there are three main options:
A batch heater employs a storage tank for collection; a direct pump system moves water from a collector to a storage tank; and a thermosiphon system uses gravity, and no pump.
If temperatures are low enough to cause freezing, then drainback or closed loop systems with heat exchangers and antifreeze will be required.
Drainback systems use distilled water to transfer heat, while closed loop systems circulate antifreeze and use a heat exchanger to transmit the heat to prevent freezing .
Most people choose to have solar photovoltaic (electricity-producing) panels installed on the roof of their homes as this provides elevation and consequently less chance of the panels being shaded by surrounding buildings and trees.
If the panels are at the same angle as the roof, they are afforded better protection from the wind, and are less likely to be damaged.
There are, however, some limiting factors: the roof must provide sufficient space to accommodate the solar panels, the roof structure needs to be strong enough to support the weight of the solar panels, and the roof must face the sun (face south in the northern hemisphere and north in the southern hemisphere), and it must be unshaded for most of the day.
If solar panels are at a different angle to the roof, planning permission may be required.
Non-roof-mounted solar panels allow for increased flexibility in placement and are suitable for use in circumstances where the roof does not meet the above requirements .
While solar panels are expensive to install, once installed they require very little maintenance, and will yield value for many years to come – the resultant savings on electricity bills could quickly exceed the cost of installation and maintenance.
In addition, rebates and tax credits are often available, with a tax credit of 30% of the cost offered in the United States. Households with large electricity bills will experience the greatest financial return on this investment.
Solar panels can also greatly increase the value of a house, with potential buyers seeing the potential electricity saving as a huge incentive.
Having a solar electric system installed by a company is expensive, so many people prefer to buy DIY kits, or to build their own.
For those that are not daunted by technical details, the task of building a DIY solar panel can be completed in a very short time. Solar panels can be easily constructed using parts obtained through Amazon, eBay, or from the local hardware store.
The most expensive component of a solar panel is the solar cells, which are made from crystalline silicon and conducting metals that convert sunlight to electricity.
To save costs, blemished or damaged solar cells in working condition can often be picked up at a much lower price than the cost of cells that are in perfectly new condition.
A total of 36 3’x6’ solar cells will be required for a complete solar panel (other sizes are available and can be used, just make sure you buy cells of uniform sizes and wattage).
The cells should be wired in series by soldering, leaving some space between the cells to allow for expansion when they are heated by the sun.
Normally each cell will generate roughly 0.5 volts, so 36 cells in series will produce around 18 volts, which is sufficient to charge a 12 volt battery.
Other equipment that is necessary to complete the system include: an inverter to convert the DC current of the solar panels to AC current used by household appliances; deep-cycle batteries to store surplus energy; and a charge converter to ensure that batteries are not overcharged, or excessively drained.
Once the solar cells are wired together in series, they are attached to a backing-board and secured in a protective box casing built to house your solar cells.
This must be shallow enough to allow sunlight to reach the cells without being inhibited by the sides.
The front of the protective box casing is covered with a durable clear plexiglass front to protect the unit from the weather.
You’ll need to weatherproof your unit by sealing the joins with silicon and painting the backing board if you’re using plywood.