Solar Cells!Solar Cells!

The epic struggle between The epic struggle between man and plant.man and plant.

My, that’s brightMy, that’s bright

• The sun does more than brighten our The sun does more than brighten our dayday

• It:It:– Heats the planetHeats the planet– Is partly responsible for all things about our Is partly responsible for all things about our

climateclimate– And of course it keeps stuff aliveAnd of course it keeps stuff alive

•Plants, algae, some bacteria, and some protists Plants, algae, some bacteria, and some protists use it directly for food. (photoautotrophs)use it directly for food. (photoautotrophs)

Plants eat sunshine?Plants eat sunshine?

• How does a plant use sunshine for How does a plant use sunshine for food?food?– Water + COWater + CO22 + Light = Sugar (Food) + Light = Sugar (Food)– ChlorophyllChlorophyll

• Plants also produce oxygenPlants also produce oxygen– Good for us, of courseGood for us, of course

Wouldn’t it be cool to use the Wouldn’t it be cool to use the sun too?sun too?

• Humans can’t use the sun for foodHumans can’t use the sun for food

• Generally sunlight alone isn’t good Generally sunlight alone isn’t good enough to keep us alive in the winterenough to keep us alive in the winter

• How can we use the sun?How can we use the sun?

Solar Panels!Solar Panels!

• 2 main categories2 main categories– Things that use the heatThings that use the heat

•Solar hot water panelSolar hot water panel– Pools can use this to make heated waterPools can use this to make heated water– Some homes/camps can use this alsoSome homes/camps can use this also

– Things that use the lightThings that use the light•Solar cells or photovoltaicsSolar cells or photovoltaics

•This is what I want to talk about!This is what I want to talk about!

Solar Cells: Hey! I’ve heard of Solar Cells: Hey! I’ve heard of those!those!

• Solar panel-powered electronics have Solar panel-powered electronics have become fairly commonbecome fairly common– Calculators for instanceCalculators for instance

• Spacecraft almost always have some Spacecraft almost always have some sort of solar panel on themsort of solar panel on them

• Less commonly houses/camps use Less commonly houses/camps use them for electricitythem for electricity

How do they work?How do they work?

• They don’t produce sugarThey don’t produce sugar

• They produce electronsThey produce electrons– Electrons power everything electricalElectrons power everything electrical

• Electrons are either used or stored in Electrons are either used or stored in a batterya battery

How do they work?How do they work?

How do they work?How do they work?

• Single panels usually aren’t enoughSingle panels usually aren’t enough

• Multiple panels are used to get more Multiple panels are used to get more voltage or powervoltage or power

The future of solar panelsThe future of solar panels

• Solar energy is not very popular for Solar energy is not very popular for anything larger than a calculatoranything larger than a calculator

• Research in more efficient, cheap Research in more efficient, cheap materials are sure to make this materials are sure to make this technology more widespreadtechnology more widespread

The EndThe End