Energy is in everything and comes in different forms. It comes in the form of heat (thermal), light (radiant), mechanical, electrical, chemical, and nuclear energy. There are two groups of energy – renewable and non-renewable. Solar, wind and geothermal energy, biomass, hydropower and tidal energy are sources of renewable energy. However we get most of our energy from non-renewable energy which includes the fossil fuels -- oil, natural gas, and coal.
 Why should I be aware of this?
- Energy is very important in every aspect of our lives. We need to be adequately armed with basic knowledge about energy to make informed decisions or determine what can be done to manage and conserve energy resources.
- Energy and environment are essential for sustainable development.
- The poor are disproportionately affected by environmental degradation and lack of access to clean and affordable energy services.
- Energy affects global issues such as as climate change, biodiversity and ozone layer depletion.
- Most fossil fuels are relatively plentiful and inexpensive. But combustion of fossil fuels generates numerous air pollutants as well as gases that may contribute to global climate change.
- Coal mining has posed hazards not only to its workforce but also to the environment. Thanks to stricter regulations, improvements have been made, but disturbances to soil, water, vegetation, and other resources during extraction are still significant
- The burning of coal at electric-generating plants also contributes to air particulates and acid rain.
- Tanker spills during ocean transport can significantly impact marine ecosystem and coastal environments over a wide area. Even more oil is spilled each year during and after use, and via storm runoff.
 All about energy
Energy can be generated both through renewable and non renewable sources.
 Non renewable sources of energy
Non renewable energy sources come out of the ground as liquids, gases and solids. These include coal, petroleum, natural gas, and propane, which are also called fossil fuels. This is because they were formed from the buried remains of plants and animals that lived millions of years ago. Uranium however, is mined and converted to a fuel for nuclear energy. Energy sources that cannot be replenished in a short period of time are called non renewable. These include
- Natural gas
- Nuclear energy
 Renewable sources of energy
Renewable energy sources can be replenished in a short period of time. The five renewable sources used most often are:
- Solar energy
- Wind Energy
- Geothermal Energy
- Biomass and biofuels including wood and wood waste, municipal solid waste, landfill and biogas, ethanol, and bio-diesel.
- Water ( Hydropower; tidal energy)
In the past, renewable energy has not been used as much as non renewable resources because
- They are generally more expensive to use than fossil fuels.
- They are often located in remote areas and it is expensive to build powerlines to the cities where they are needed.
- They are not always available. For example, cloudy days reduce solar energy, calm days mean no wind blows to drive wind turbines and droughts reduce water availability to produce hydroelectricity.
The production and use of renewable fuels has grown more quickly in recent years due to higher prices for oil and natural gas.
 Uses of energy
- Commercial - buildings
- Industry and Manufacturing
- Transportation- cars, trucks, planes, etc.
In developed countries such as the US, the industrial sector uses about one-third of the total energy. The residential and commercial sectors combined use 40 % of all energy. Energy used for transportation accounts for more than a quarter of all energy produced in the country.
 What can I do?
We need to save energy. This can be done through
- Balanced community energy plans that incorporate conservation and efficiency initiatives.
- Practicing "The Three 'Rs'— Reduce usage and potential waste; Reuse, rather than discard materials; and Recycle materials. Apart from saving energy, households and businesses lessen landfill waste and conserve natural resources.
- Following the Three Rs decreases pollution by reducing the need to manufacture, distribute, and use materials from raw resources.
- Energy efficiency increases when energy conversion devices, such as appliances or car engines, undergo technical changes that allow them to provide the same service while using less energy.
- Residential and commercial buildings account for more than a third of U.S. energy demand. The energy efficiency of buildings can be enhanced through the use of insulation, appropriate landscaping, and design improvements.
- Efficient lighting saves on air conditioning and electricity.
- For most industries, energy is a small part of operating costs, so there is little incentive to conserve. But cogeneration is an area where industry could save both energy and money.
- Providing electricity, light, heat, or mechanical energy near their point of use lessens the need for transmission lines and pipelines. Such "distributed" energy may use renewable resources, or it may incorporate alternative uses of traditional energy, such as natural gas micro-turbines for small businesses.
- Between 1850 and 1970, world population multiplied by 3.2 times, and total energy use increased became twelve fold.
- More than 90% of the energy produced and consumed in the world today is from non renewable sources.
- Coal was formed from the remains of plants that lived in vast swamps some 350 million years ago. Over time, the sediments became rock and their weight generated heat and pressure on the material below, transforming the carbon of the decayed plants into coal.
- Coal is still responsible for some 35% of world carbon dioxide emissions from fossil fuels.
- Half of the savings due to automobile fuel efficiency increases from 1972 to 1992 were cancelled out by decreases in vehicle occupancy.
- Though accounting for only 5% of the world's population, Americans consume 26% of the world's energy.
- Worldwide, some 2 billion people are currently without electricity.
- Developing countries use 30% of global energy. Rapid population growth, combined with economic growth, will rapidly increase that percentage in the next 10 years.
- The World Bank estimates that investments of $1 trillion will be needed in this decade and upwards of $4 trillion during the next 30 years to meet developing countries' electricity needs alone.
- Buying an efficient air conditioner or furnace will automatically reduce energy consumption -- This might not be true if the equipment is not sized or installed properly.
- Energy efficiency and energy conservation is one and the same thing -- Energy efficiency means getting a job done with less energy. This could be lighting a room, cooling a house, or refrigerating. Energy conservation, on the other hand, means reducing the level of services, e.g. reducing lighting or comfort or turning up the temperature of your fridge.
- Halogen lighting is super-efficient -- It is true that halogen lights use slightly less energy than standard incandescent bulbs, but halogens require transformers that can use extra energy, even when the light is off. They are also a fire hazard. By comparison, compact fluorescent lights are nearly three-times as efficient and don't pose a fire hazard. Many new models are dimmable, like halogens
 Energy and pollution
Almost all energy production and use involves some form of pollution of our environment.
Coal & Oil Power Plants
Release pollutants such as
- Carbon dioxide which causes global warming.
- Nitrous Oxide causes smog
- Dust particles might cause lung cancer and other lung ailments.
Nuclear Power Plants
- Radioactive Waste (liquid or solid) that is difficult to dispose of.
- Radiation leaks that can cause radiation poisoning and increased risk of cancer.
- Heat emissions in water. This can causes growth of algae and kill marine life.
 Ageing energy
It has been proven that like matter, energy never increases or decreases but remains constant. So does that mean we can at least be assured of the total amount of energy available to us that can be tapped in some form or the other? This is not so. As energy changes form, it ages. This means that any energy resource must be finite, and must run out if used often enough over a long enough period of time. The net result of any energy changes must be an increase of entropy and the resulting energy will be less useful and more difficult to use than before.
- What is Energy?
- Some Basic Energy Information
- Aging of Energy
- SEI Energy facts
- Environment and energy
- Energy Myths