Renewable Energy: Solar Energy

Types of Renewable Energy Solar Water Wind Biomass –b–b–b–burning –c–c–c–conversion to liquid fuels Geothermal Solar-Hydrogen

Current Sources of Energy

Direct Solar Energy Used toUsed to – Heat houses and buildings – Heat water – Create high temperature heat – Create electricity

Methods of creating electricityMethods of creating electricity – Biomass Energy – Wind Energy – Hydropower – OTEC – Waves & Tides Indirect Solar Energy

Passive Solar Heating Uses special materials, design orientation and space to utilize solar energy.Uses special materials, design orientation and space to utilize solar energy. Considers exposure direction, windows, building materials, eavesConsiders exposure direction, windows, building materials, eaves Requires NO input of energyRequires NO input of energy East CoastEast Coast

Trombe Wall Passive heating system where a massive wall is built behind a window exposed to the sun that will retain and re- emit solar heat.Passive heating system where a massive wall is built behind a window exposed to the sun that will retain and re- emit solar heat.

Extended Eaves Passive heating that blocks the summer sunPassive heating that blocks the summer sun

Water Heating Flat box with glass on top, black on the bottom, water tubes in middleFlat box with glass on top, black on the bottom, water tubes in middle –Hot water coming out of tubes is placed in top of water tank –Cooler water from bottom returned to collector

Passive Solar Heating Solar CookersSolar Cookers –metal lined box and mirrors focus solar energy to cook food

Fresh Water Solar Ponds Passive: Holes are dug and lined with black plastic. – –Water heats up, but heat is prevented from escaping with insulating panels. Doesn’t require expensive storage

Active Solar Heating Input of energy to gain full benefits from solar heating.Input of energy to gain full benefits from solar heating. Ex: using pumps or fans to utilize sun energyEx: using pumps or fans to utilize sun energy

PV Cells: Active Heating Photovoltaic cells When photons from sun hit a thin wafer of metal, a small elec. current is produced Many cells must be linked to prod usable energy Used in remote areas, calculators, watches

Solar Cell Backpack Anyone? It will charge your iPod

PV Solar Cells Pros: used in remote areas, no greenhouse gas emissions emitted, noiseless Cons: initial cost, much land is needed, many must be used to be efficient, wears down over time, breaks easily, materials aren’t recyclable.

Grid vs Stand Alone PV Cells Grid: PV Cells linked together; can send power back to city’s lines. Can get $$Grid: PV Cells linked together; can send power back to city’s lines. Can get $$ Stand Alone: PV cell by itself (not connected to city’s power). Needs a battery to store energy when sun not available. (Hg)Stand Alone: PV cell by itself (not connected to city’s power). Needs a battery to store energy when sun not available. (Hg)

Active Heating Solar TowersSolar Towers –many mirrors are used to focus solar energy  heats oil  turbine

Solar-Hydrogen Energy- Theory H gas used for energy in 2 ways: ––b––burned directly - since no carbon, it burns cleanly ––c––combined with oxygen gas to produce water (fuel cells) Problems: ––H––H 2 gas is costly to make through chemical rxns

Fuel Cell Device that takes H and O to make electricity. Byproduct = water & heat. Fuel Cell Car

Fuel Cells Pros: 1. 1.No CO 2 emitted 2. 2.H can be produced from water 3. 3.High efficiency Cons: 1. 1.H is very flammable 2. 2.H not found alone in nature 3. 3.Energy is needed to produce fuel (from water) 4. 4.No distribution system in place.