IT CAN safely be said that today’s world runs on energy. In every sphere of life, the consumption of energy is probably the highest of all resources used by man – at home, in schools, hospitals, shopping centres, factories, businesses, transportation and leisure. Most of this energy comes from the burning of fossil fuels such as coal and oil which are non-renewable sources. The use of fossil fuels has a definite impact on the environment as it often leads to destruction of natural habitats such as caves, where coal mining is done, and other resources such as waterways and the life within them, in the case of accidental oil spills. In addition to this, fossil fuels contribute significantly to climate change which is probably the greatest threat to life on earth as we know it, in this era. Clean, renewable sources of energy which will significantly reduce dependence on fossil fuels and also have a less negative impact on the environment are therefore being sought.
What are the options?

The most common and widely used sources of renewable energy are probably solar energy followed by hydropower and wind energy. Less commonly utilized are geothermal energy and biomass.

Solar energy
Solar energy is derived from the sun which generates a tremendous amount of energy as a result of the nuclear fusion of hydrogen taking place within its core. This energy can be converted to thermal or heat energy by photovoltaic or solar cells which change sunlight directly into electricity. Solar energy is increasingly being utilized in the world today. In Guyana, the recently installed stoplights are equipped with solar panels which provide the energy for their operation. In addition, several hinterland communities and even businesses in Georgetown are using solar energy in their operation.

Wind energy
Wind energy or wind power is the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks such as grinding grain or pumping water or a generator can convert this mechanical power into electricity to power homes, businesses and schools. 
Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current. Simply stated, a wind turbine is the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
Like solar energy, several countries in the world are making use of wind energy. There are huge wind farms in the United States, China, the UK and Denmark and they supply a substantial amount of   energy requirement for those countries. 

Hydropower
Hydropower is produced by channeling moving or running water to create mechanical energy which is then converted into electricity by generators. Today, rivers and streams are re-directed through hydro generators to produce energy. The fall or flow of water determines the amount of available energy. Dams are built across a lake or river to trap water which then flows through tunnels and turn turbines to produce electricity.
The amount of available energy in moving water is determined by its flow or fall. Swiftly flowing water in a big river carries a great deal of energy in its flow. Water descending rapidly from a very high point, like Kaieteur Falls also has lots of energy in its flow.
In either instance, the water flows through a pipe, or penstock, then pushes against and turns blades in a turbine to spin a generator to produce electricity.

Geothermal
Holes are drilled down to the hot region, steam comes up, is purified and used to drive turbines. Hot rocks underground heat water to produce steam. The first geothermal power station was built at Landrello, in Italy, and the second was at Wairekei in New Zealand. Others are in Iceland, Japan, the Philippines and the United States.
This type of energy comes from heat within the earth and is generated by the earth’s core below the surface. Temperatures hotter than the sun’s surface are continuously produced inside the earth by the slow decay of radioactive particles, a process that occurs in all rocks. This energy is obtained by digging wells and pumping the heated underground water or steam to the surface

Biomass
Biomass is biological material from living, or recently living organisms, such as wood, waste, (hydrogen) gas, and alcohol fuels. It is common that plant matter is grown to generate electricity or produce heat, usually by direct incineration. Forest residues, such as dead trees, branches and tree stumps, yard clippings, wood chips and garbage are often used for this.
Biomass also includes plant or animal matter used for production of fibers or chemicals. When burnt, the chemical energy in biomass is released as heat which turns turbines to generate electricity. Other usable forms of energy such as transportation fuels, ethanol and surface.biodiesel can be made from Biomass.
The initial cost to develop the facilities for renewable energy may be large. However, the long term cost and benefits to humans and the environment is worthwhile.
Guyana has made an effort to utilize renewable energy over the years. In this regard, small scale hydropower facilities have been set up in some hinterland locations in the country and plans are already being implemented for a large scale hydropower operation to feed into the national grid and reduce dependence on fossil fuel in the future.                             
You can share ideas and questions by sending your letters to: ‘Our Earth, Our Environment’, C/o EIT Division, Environmental Protection Agency, Ganges Street, Sophia, GEORGETOWN, or email eit.epaguyana@gmail.com