What sort of sustainable energy sources or resources are the cleanest and most economically viable ?

Question

Since petroleum oil is becoming less affordable and is believed by many to be the main cause for global warming, what do you think should replace petroleum oil and gas?

Answer 1

The most appropiate type of alternative energy source will be dependant on the application. I will assume you are refering to alternative energy for use in vehicles. Currently there are a few alternatives, some in the early phases of implementation, others a long way off. In the end different techonoligies will develop in parallel to maturity. These include:

1) Hybrid vehicles (petrolium based/electric hybrids) - very economical, they recover energy in breaking in a dynamo to charge the battery bank and a gas or diesel engin for the main power source.

2) Bio-fuel - primarly bio diesel from soya oil, or Ethanol from corn or biomas. This is sustainable but requires agrigulctural land to supply the soya, maize, etc. Regular diesel vehicles can use bio-diesel with minimal modifications required. Gas powered cars can use a gas/bioethanol blend very easily with minimal modifications required.

3) GTL (synthetic) diesel - made from natural gas that may otherwise have been flared (burnt). This is a low sulphur, low aromatic, cleaner burning diesel. Many petrolium companies including Sasol-Chevron and Shell are developing this technology. See the site http://www.sasolchevron.com/ . Regular diesel cars can use GTL diesel without any modifications required.

4) Hydrogen powered cars - based on the hydrogen fuel cell require a source of hydrogen. They have no emissions (except water) and low noise also. To make hydrogen you need energy and this would have to come from a clean source. There is a lot of water availible, but you need electricity to split water into hydrogen and oxygen. Currently the only really viable source would be nuclear power. If in the distant future fusion reactors could be comercialised, they could provide the energy for battery/hydrogen powered cars. There are still some problems to solve so this is a longer term possibility. Other problems include how to store hydrogen in the vehicle safely. Its a highly flammable gas and would need to be stored under high pressures. Current vehicles would have to be significantly modified to run on hydrogen. The method of using the hydrogen would be using a hydrogen fuel cell that generates electricity from the hydrogen. The car would use an electric motor.

5) LPG (liquified propane gas) - this fuel combusts (burns) in the engine like gas. LPG is expensive to produce and transport though it could be used in modified engines.

These are the main alternatives currently availible.

Answer 2

Lets postulate, cars will be electric and will get it from a socket at your house. That most cars will be hybrids that make hydrogen from elecrticity and water to store the energy. Then:

Sun.

But before that becomes truly economically viable we have to wait a few years. Specially the 'mobile'-versions are really expensive and have low yield.

Wind is nice but expensive. (maintenacewise and needs lots of space because it is loud)

Hydroelectricity (electrics generated by 'falling water' in dams) got the best credentials the last 50 years or so. It mostly needs major environmental change (large flooded area's mainly) so there is some discussion about if it is real environmentally friendly.

Norway does about all it's energy that way.
Canada is the biggest with 341,312 GWh

You could run loads of cars, millions of miles on that kind of zap-power.

Answer 3

Hydrogen based energy production seems to be the most viable at this time...Our planet is 2/3 water and Hydrogen makes up 2/3 of this. Separating Hydrogen from water is very simple and can be done in your on home. Also, using Hydrogen as a fuel would not require us to change our current technology as it is a combustible. However there are some problems with this in that it is very unstable and requires better containment and safety technology, and given that the world economy is based on Oil, even if we could and wanted to change over to this it would have to be done very slowly so as not to collapse the economy.

Answer 4

Wind Solar & Tidal power. The UK is surrounded by the sea and we get a fair bit of wind and some sun (now & then) so I think we realy should make better use of all three of the above. I think every newly built home should have solar panels on the roof and a small wind turbine too to provide at least 50% of the energy sources to heat and power the house.

Answer 5

Check out www.permanentenrgy.com
Closed circuit hydroelectric power, it's fuel-less 1,000,000 mega watts and pollution free. Thats 1000 times more than Nuclear and even more than Fusion.
The government has snubbed this power source because it makes overabundant electric power cheaper than any fueled process. Today's polluting power that has bought our pollitions and doesn't want this on the market. So every pollititon just will see it even though it was put in front of Clinton, Gore, Newt, Sam Nun, Congressman Walker, DOE, and Bush's administrtion will not return any attempts at contact, calls or emails.
Look at "Manhattan Project needed" in yahoo news under science and check out my post.

Answer 6

Propane. its clean, efficient, and proven not to contribute to the well-known problem of global warming.

Answer 7

Biofuels such as methanol will probably be the easiest to convert cars to.