Chapter 5 - Natural Resources
We need to answer several questions in deciding which energy resources to promote.
1. It takes at least 50 years and huge investments to phase in new energy alternatives to where they provide 10–20% of total energy use (shifts in the use of energy resources in the US since 1800).
2. The following questions must be answered for each alternative:
a. How much of the energy resource is likely to be available in the near future and in the long term?
b. What is the net energy yield for the resource?
It takes energy to get energy. (Categories of the quality of different sources of energy)
The useable amount of high-quality energy available from a given quantity of an energy resource is its net energy.
Net energy is the total amount of energy available minus the energy needed to extract, process, and get the energy to consumers.
Net energy can be expressed as a ratio of useful energy produced to the useful energy used to produce it.
Net energy is like your net spendable income (your wages minus taxes and other deductions.
For example, suppose that for every 10 units of energy in oil in the ground we have to use and waste 8 units of energy to find, extract, process, and transport the oil to users.
Then we have only 2 units of useful energy available from every 10 units of energy in oil.
The net energy ratio would be 10/8, or 1.25. The higher the ratio the greater the net energy.
When the ratio is less than 1, there is a net energy loss.
Estimated Net Energy Ratios
Currently, oil has a high net energy ratio because much of it comes from large, accessible and cheap-to-use deposits such as those in the Middle East.
When those deposits are depleted, the net energy ratio of oil will decline and prices will rise.
Then more money and high-quality fossil fuel energy will be needed to find, process and deliver new oil from:
deposits that are small and widely dispersed, buried deep in the earth's crust, and located in remote areas or further off-shore.
extracting and processing shale oil.
Nuclear Energy has a low net energy ratio because large amounts of energy are needed to:
extract and process uranium ore
convert it into a useable nuclear fuel
build and operate nuclear power plants
dismantle the high radioactive plants after their 15-60 year useful life
store the resulting highly radioactive wastes safely for 100,000+ years
c. How much will it cost to develop, phase in, and use the resource?
d. What government research and development subsidies and tax breaks will be used to help develop the resource?
e. How will dependence on the resource affect national and global economic and military security?
f. How vulnerable is the resource to terrorism?
g. What are the affects of extracting, transporting, and using the resource on human health and the earth’s climate?
New Technology Changes