In recent years, international climate policy has increasingly focused on limiting temperature rise,as opposed to achieving greenhouse-gas-concentration-related objectives. The agreements reached at the United Nations Framework Convention on Climate Change conference in Cancunin 2010 recognize that countries should take urgent action to limit the increase in global average temperature to less than 2 ◦ C relative to pre-industrial levels.
It took 3000 year for raise of 6 degree temperature at global level but it took just 100 years for global temperature to rise to another 6 degrees. It is expected that global temperature shall raise another 5 degrees in next 100 year period ( 2000 to 2100). The Carbon-dioxide level which was 280 ppm 100 years ago has gone up to 385 ppm and is still rising. 40 percent of the electricity in the world is produced by thermal process utilizing coal as fuel. Only 6 percent of renewable energy sources which include solar, biomass, geothermal, tidal and hydroelectric provide energy. 20 percent of the Corn in USA provides only 1 percent of the energy need and even if entire corn is used for producing biofuel it will cover only 7 percent of biofuel needs.
There can be four possible energy plans in the present context:
ENERGY PLAN A – Fossil Fuel Based: Use of “non renewables” sources of energy. Develop tar sands, oil shale, nuclear energy and bury CO2 in ocean and land. Top Priority is “clean” coal. CO2 from coal – 2x natural gas. This is largely view of corporate sector.
(a) Alternatives –Natural Gas:
Natural gas is used primarily for space heating, electricity generation; Natural gas is the key ingredient in agricultural fertilizers. Main material for hydrogen (natural gas – 48%, oil – 30%, coal – 18%). However it is not a viable replacement for oil – hard to ship. It is more suited as regional fuel . U.S. only imports from Canada and Mexico via pipeline. Natural gas was one of the key solutions to the oil shock of the1970s . It can be used in automobile engines. Honda is selling a natural gas Civic with home gas dispenser.
(b) Alternative – Nuclear: Nuclear Energy – Only “new” (1945) energy source in centuries – U235. Relatively “safe” when operating – No new Chernobyl or 3 Mile Island. But accidents could be catastrophic. Price-Anderson Act law in1957 passed exempting liability Still in force – utilities won’t build new plants without it. Uranium will be available for some decades – but not forever. However fundamental issue is radioactive wastes which last for thousands of years. Lots of hype – Fusion reactors, breeder reactors. No successes after decades of efforts – $billions wasted. Number of reactors needed to carry most of load is phenomenal i.e. 6300 reactors may be needed globally until in next 50 years to keep present level of supply.
ENERGY PLAN B: This includes “renewables”. They are ecofriendly and “Environmentally”
They also include wind and solar. Some consider it as burning of food. However they provide clean carbon neutral and a biofuel free from SPN, NOx (sometimes) , S02 and have high cetane and octane value. Mass transit, fuel cells, PHEVs and supported by many Solar and Wind companies and many NGOs.
(a) Alternatives – Wind and PVs: Wind turbines the most efficient options – and fastest
Growing, 2/3 of projected alternative supply is wind.
Photovoltaics (PVs), PVefficiency went from 8% to 16% in first 10 years – little improvement since and its price also become stable. Most renewables generate only electricity. PV are less flexible than oil or naturalgas.
(b) Tidal power inareas of large tides utilizes waves to move turbines. They can be built anywhere on offshore areas.
(c) Geothermal : Heat near surface of the earth = geysers, volcanoes, hot springs are basic sources. Japan,Iceland, New Zealand are big users of geothermal energy. Heat is used to make steam to turn turbine for electrical generation.
(d) Alternatives – Dams: They have major ecological effect –destruction of species. Stiff resistance is observed for construction of dams as they destroy many homes and displace populations and ecosystems. Dams are eventually filled with silt and are not “renewable”. Forced relocation of people causes enormous hardships to the population. Nobody in US is proposing dams.
ENERGY PLAN A AND B –Common Points: Fuels or new sources (A or B Technology) can utilize Plan A – Clean Coal, Tar Sands and from Plan B – Biomass, Biofuel, Lignocellulosic waste, Bio ethanol, Bio methane, Algal biofuel , Switch Grass, Wind and Solar energy. Nuclear power is supported by both to some degree. There is lots of overlap between the two e.g.GE Biggest Wind Turbine Company and Biggest Power Plant (coal, gas, nuclear) Company. Development will require more energy at various levels and we don’t have to consume less energy –just different energy.
Understanding Net Energy: It takes energy to process fossil fuels for usage and cheapest energy cost to process fuels is in crude oil in middle east. Most expensive energy cost to process fuels are the non-conventional fossil fuels. Besides there is energy cost involved in production of bio-diesel. It is vital to understand the concept of net energy. This explains poor prospect for many alternatives which consume considerable fossil fuel energy for their production.
Cultivation of biofuel leads to topsoil depletion – currently we are depleting the soil 20 times faster than it is being replaced. This is already resulting in skyrocketing of food prices.
Future prospects: Cellulosic ethanol – Still technical limitations, takes about five times as much energy required to make cellulosic ethanol than the energy contained in the ethanol.
PLAN C Conserving inCommunity: A view of only using enough.
Conserving, Sharing&Saving ofenergy is one of the important option for our future.