Solar energy

Solar EnergyA Natural, Renewable

Resource

Valerie Stannard

Facts:

Within the next 40 minutes, the U.S. will receive more energy in the form of sunlight than it burns in a full year from fossil fuels.

The Sun delivers 17,000 million MW of energy to the earth each year.

Solar architecture dates back to 2500 BCE and was used by many civilizations.

Da Vinci predicted a solar industrialization as far back as 1447.

So why don’t we use it?Common myths:

Solar-powered life requires sacrificing modern conveniences.

Solar-powered homes have all the appliances that other homes have.

ex. washers, dryers, computers, television sets, refrigerators , etc.

So why don’t we use it?Common myths:

You need storage for solar power for power at night.

There is a net metering system that allows the utility companies to "absorb" the energy your system would generate, and then credit you for the energy you need supplied.

Consumption of energy is supplied from the power grid at any time during the day or night. First the credits are used up, and you pay only for the excess usage.

So why don’t we use it?Common myths:

Electricity from solar power is expensive.

Nothing is cheap in these days. It’s still found to be less expensive to install

a solar system than connect to the grid if you are more than about 500 yards from a utility connection.

So why don’t we use it?Common myths:

Solar power isn’t entirely developed.

No technology is ever ‘finished.’ Solar energy generation is a fairly mature technology at present, but research and development continues, of course.

What percentage of world energy consumption and electricity generation

comes from renewable energy?

In 2008, the EIA estimated that the world consumed 504.7 quadrillion Btu of energy, where 10% was renewable energy.

By 2035, it’s forecasted that consumption of renewable energy will be about 14% of total world energy consumption.

How much energy does a person use in a year?

In 2010, total energy use per person in the U.S. was 317 million British thermal units (Btu).

Why Don't We Use More Renewable Energy?

Renewable Energy Technologies Are Capital-Intensive.

generally more expensive to build and to operate than coal and natural gas plants.

Renewable Resources Are Often Geographically Remote.

building transmission lines to deliver power to large metropolitan areas is expensive.

Solar Energy Can Be Used for Both Heat and Electricity.

Heat

Heats water for homes, pools, and buildings.

Heats spaces such as houses, greenhouses, and buildings.

http://www.biofuelswatch.com/how-does-solar-energy-work/

Electricity PV devices or “solar

cells” change sunlight directly into electricity.

Can be applied in three ways:

Stand-Alone. Commonly called Solar

Home Systems (SHS) A system not connected

to the grid. Grid-Connected.

Homes are connected to the grid for if there is ever a need.

Back-Up. Used for areas with

unreliable grids.

http://ehowtomakesolarpanels.com/information-center/

How do solar panels work?

1.) Sunlight hits the solar panels (also know as a photovoltaic/ PV) and are absorbed by semi-conducting materials such as silicone.

2.) Electrons are knocked loose from their atoms, which allow them to flow through the material to produce electricity.

Also called the photovoltaic (PV) effect.

How do solar panels work, cont.

3.) An array of solar panels converts solar energy into DC (direct current) electricity.

4.) The DC electricity then enters an inverter.

5.) The inverter turns DC electricity into 120-volt AC (alternating current) electricity needed by home appliances.

6.) The AC power enters the utility panel in the house.

How do solar panels work, cont.

7.) The electricity is then distributed to appliances or lights in the house.

8.) When more solar energy is generated that what you're using - it can be stored in a battery as DC electricity. The battery will continue to supply your home with electricity in the event of a power blackout or at nighttime.

9.) When the battery is full the excess electricity can be exported back into the utility grid, if your system is connected to it.

10.) Utility supplied electricity can also be drawn form the grid when not enough solar energy is produced and no excess energy is stored in the battery, i.e. at night or on cloudy days.

How do solar panels work,

cont.

11.) Any surplus energy is sold back to the utility company.

Facts about Solar Energy Usage:

Solar Energy is measured in kilowatt-hour. 1 kilowatt = 1000 watts.

1 kilowatt-hour (kWh) = the amount of electricity required to burn a 100 watt light bulb for 10 hours.

According to the US Department of Energy, an average American household used approximately 866-kilowatt hours per month in 1999 costing them $70.68.

About 30% of our total energy consumption is used to heat water.

Facts about Solar Energy Systems:

A home solar system is typically made up of solar panels, an inverter, a battery, a charge controller, wiring and support structure.

A 1-kilowatt home solar system consists of about 10-12 solar panels and requires about 100 square feet of installation area.

A 1 kilowatt home solar system will generate approximately 1,600 kilowatt hours per year in a sunny climate (receiving 5.5 hours of sunshine per day) and approximately 750 kilowatt hours per year in a cloudy climate (receiving 2.5 hours of sunshine per day).

A 1-kilowatt home solar system will prevent approximately 170 lbs. of coal from being burned, 300 lbs of CO2 from being released into the atmosphere and 105 gallons of water from being consumed each month!

Pros and Cons of Solar Energy

Pros Environmentally

friendly.

Low to no maintenance.

Saves you money in the long run.

Cons High installation costs. The production of

solar energy is influenced by the presence of clouds or pollution in the air.

Solar panels require quite a large area for installation to achieve a good level of efficiency.

http://www.fsec.ucf.edu/en/media/enews/2007/2007-04_Sunshine_state.htm

Why Should I Convert to Renewable Energies?

Incentives are available form state, federal and local governments, as well as some utility companies.

Go to the DSIRE website to find out what’s available in your area (USA only).

Solar energy systems do not produce air pollutants or carbon-dioxide.

When located on buildings, they have minimal impact on the environment.

Just how much does solar energy cost to acquire?

It varies on: Size of your household.

Amount of electricity you use.

How much sun your area receives.

Available Government funding.

Rough Estimates: A solar hot water system will cost

between US $2,000 and $4,000.

A photovoltaic system will cost between US $8,000 and $10,000 for a 1kW system. (or $8 - $10 /Watt)

PLEASE NOTE that these prices are only estimates and will vary depending on many different factors that needs to be taken into account for each specific installation.

An average American family, living in a 3-bedroom home will require a 1.5 - 3kW system, which will cost between US $13,000 and US $27,000, before rebates.

Sources Solar Renew Energy. Nonprofit Office.net, n. d. Web. 29 Feb. 2012.

<http://www.pasolar.org/>.

"Top 5 Misconceptions about Solar Power." Solar Energy.Org. Cooler Planet, n. d. Web. 29 Feb. 2012. <http://www.solarenergy.net/Articles/top-5-misconceptions-about-solar-power.asp&xgt;.

U.S. Energy Informations Administration. U.S. Deaprtment of Energy, n.d. Web. 29 Feb 2012. <http://www.eia.gov/>.

"Discover everything Solar Energy Advantages Disadvantages ." Facts About Solar Energy. N.p., 2005-2006. Web. 12 Mar 2012. <http://www.facts-about-solar-energy.com/index.html>.