Renewable Energy

Alternatives to Fossil Fuels for generating electricity are vital as we continue to damage our o-zone layer and exhaust supplies of coal, gas and oil. Engineers have developed a wide range of alternative, sustainable energy sources that may future proof our planet.

Solar energy can be used as a thermal source or for electrical generation. Photovoltaic (PV) is a way of capturing the photons of light radiated by the sun to generate electricity. Solar panels consist of layers of silicon which are designed to take advantage of the 'photoelectric effect' to generate DC electricity.

Advantages of Solar Panels - No mechanical parts, Long life span (~10 years), Thin and lightweight, completely renewable, no bi-products, low maintenance, recyclable at end of life

Disadvantages of Solar Panels - Low efficiency (~40%), Weather dependant, Downtime at night, high cost on large scale, lifespan of around 10 years, must be kept clean

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Solar energy can equally be used as a source of Heat energy in homes through the use of Solar Heating Systems.Thermal collector panels are fitted externally to a home and a solar fluid is constantly pumped through them to absorb photons from the sun and transfer heat to the water tank.

Advantages of Solar Heating - Reduction in energy cost, No bi-products, sustainable, minimal maintenance, highly efficient (70-90%), low cost in comparison to PV

Disadvantages of Solar Heating - Weather dependant, seasonal, cannot be used exclusively, mechanical parts - pump maintenance required, storage cylinder required

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Geothermal Energy makes use of the earths super heated core and has been harnessed for thousands of years. Although initially limited to areas of tectonic plate boundries, technology has now allowed us to use it domestically all over the world. Holes are drilled down into the earths surface and the heat from the magma below can be transferred to the surface to heat buildings or at higher temperatures create steam to drive a electrical generators.

Advantages of Geothermal - fully sustainable, very efficient, can be used to regulate climate of buildings to cool and heat, low maintenance, 50% less electricity than standard heating

Disadvantages of Geothermal - High cost of installation, Depletion of heat source over time, harmful gases released from drilling can cause environmental damage, land required for drilling

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Wind Energy can be harnessed to drive propellers attached to turbine generators producing a sustainable source of electricity. Wind farms are placed either Onshore or Offshore with latter being more cost effective and producing a greater energy efficiency. It is representative of around 4% of the worlds electrical generation.

Advantages of Wind Power - Low maintenance, low running costs, susustainble, no bi-products, low space requirement, use in remote locations as primary energy source

Disadvantages of Wind Power - Low capacity (20-50%) due to wind being changeable, impact on landscape onshore, high setup/installation costs, low efficiency (~40%), impact environment

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Hydroelectric power is generated from water and the potential energy created by gravity. Large bodies of water can be dammed and released into a reservoir below, rotating turbines attached to electrical generators. Worldwide it generates around 17% of the energy created.

A Kinetic pump storage system can be used in addition to allow water to be transferred back up to the reservoir when demand for electricity is low and stored for when it increases.

Advantages of Hydroelectric Power - Low running costs, zero water consumption, output can be controlled to meet demand, no bi-products, fully sustainable, can run 24/7

Disadvantages of Hydroelectric Power - Very high setup cost, can damage ecosystems, requires constant sustainable source of water, can cause flooding, water supplies can be affected by dam

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Biomass power is generated from the combustion (burning) of waste organic matter such as plants and trees to produce heat in a thermal power system. Unlike fossil fuels, biomass produces significantly less carbon dioxide and is a renewable source of energy that is considered 'carbon neutral'.

Advantages of Biomass - makes use of waste materials, carbon neutral, low cost and more efficient compared to fossil fuels, reduces landfill waste, abundant, can be generated on domestic scale (home)

Disadvantages of Biomass - not entirely clean due to polluting emissions, can contribute to deforestation, inefficient, requires high amount of space, biomass energy plants have a high setup cost

< Video resources for further explanation

NUCLEAR POWER

Energy Storage & Generation - Renewable Energy

Mr BILLINGTON