Alternative energy

Srđan Petković, Svetlana Stevanović and Jelena RadeljićPicture from http://www.afrec.net/overview.htm

• Why we do this presentation?• What are the global problems?• What are possible solutions?• What does alternative energy mean?• What kind of alternative energy there are?

Questions that we want to respond

Global Energy Problems • no oil forever • climate changes• greenhouse gas emissions• acid rain• toxic waste• pollutions (atmospheric, water

and land)• energy costs

Solutions for these problems

• Find other sources of energy• Use nature• Reduce waste and pollution

The right solutions is:

ALTERNATIVE ENERGY

Alternative energy is an umbrella term that refers to any source of usable energy intended to replace fuel sources without the undesired consequences of the replaced fuels.

Main Forms of Alternative Energy:

• Wind power• Solar power• Hydropower• Geothermal energy• Bio-energy

Wind Power

• Humans have been using wind power for at least 5,500 years. An example are windmills.

Picture from http://en.wikipedia.org/wiki/Wind_power

• The modern wind power industry began in 1979 with the serial production of wind turbines by Danish manufacturers.

Picture from http://www.electrical-res.com/wind-turbine-power-generation/

Solar Power• Solar power is the generation of electricity

from sunlight.• It is the conversion of sunlight to electricity.• This can be :– direct as with photovoltaics-solar cells

(is a device that converts light into electric current)– indirect as with concentrating solar power

(where the sun's energy is focused to boil water which is then used to provide power)

Hydropower

• Energy in water can be harnessed and used.• Hydropower is power that is derived from

the force or energy of moving water.• Hydropower has been used for hundreds of

years as waterwheels and mills.

Some forms of water power currently in use or development:

• Tidal power - converts the energy of tide into electricity

• Wave power - is transfer of energy by ocean surface waves, and the capture of that energy. (Wave power generation is not currently a widely employed by commercial technology)

• Osmotic power or salinity gradient power is the energy retrieved from the difference in the salt concentration between seawater and river water.

Picture from http://en.wikipedia.org/wiki/Vortex_power

Geothermal Energy• Geothermal power is power extracted from

heat stored in the earth.• Geothermal power is:

cost effective, reliable, sustainable and environmentally friendly

but has historically been limited to areas near tectonic plate boundaries.

Picture from http://en.wikipedia.org/wiki/Geothermal_energy

Enhanced geothermal system 1.Reservoir 2.Pump house 3.Heat exchanger 4.Turbine hall 5.Production well 6.Injection well7.Hot water to district heating 8.Porous sediments 9.Observation well 10.Crystalline bedrock

Picture from http://en.wikipedia.org/wiki/Geothermal_energy

Bio-energy• Bio-energy is produced from materials

derived from biological sources. It is a synonym to biofuel.

• It includes biomass which is organic material, stored sunlight in the form of chemical energy.

• As a fuel it may include wood, wood waste, straw, manure, sugar cane, and many other bioproducts from a variety of agricultural processes.

Picture from http://tees.tamu.edu/index.jsp?page=news_current&p_news_id=1509

CONCLUSION

It starts with me, you and us. We can make simple changes in our everyday lives to help make a difference. First step is the use of alternative energy sources, so that’s the way how to improve and protect environment.

THANK YOU FOR YOUR TRUST!

Svetlana

SrđanJelena