STEM Sims Logo

Sun Banking

Sun Banking Thumbnail
Many homeowners face large bills from their electricity charges each month. Increasing fossil fuel costs associated with making electricity are frequently passed onto consumers in the form of higher energy bills. Many have proposed that solar power can be used to reduce traditional electricity consumption. Can you determine if solar energy is a viable energy resource? You’ll have to be bright to find out.

Investigator Icon

Planning and Carrying Out Investigations

Timer Icon

Sun Banking Brochure's Thumbnail

Sun Banking Brochure

What is electrical energy?

Electrical energy is defined as the energy associated with moving electrons through a conductor. Although electrons are continually moving in an atom, the electrons can be forced to move in a desired direction. This movement of electrons is commonly called electricity. A vast majority of device in U.S. homes operate using electrical energy. Heating and cooling homes account for the largest electricity demand, while lighting and powering devices, such as televisions and computers accounts for less than 25% of the total electrical energy used in homes.

How is most electrical energy produced?

The normal process for converting electrical energy from other forms of energy is basically the same. First, liquid water is heated and changed into steam. This step varies depending on which type of fuel is used to heat the water. Coal (most commonly used), natural gas, nuclear reactions, and petroleum are typical fuels used for making the steam. The steam is then directed towards a blade that spins. The spinning blade turns a generator that converts the mechanical energy into electrical energy via electromagnetic induction. A downside of this type of electrical energy production is the contamination of the environment due to burning the various fuels that heat the water. A second problem associated with this process is that most of the fuel sources are limited and nonrenewable, which means the fuels will eventually run out and new fuel sources will have to be found.

What is the difference between passive and active solar energy?

Passive solar energy involves the positioning of windows, shades, and other devices to maximize the amount of sunlight reaching the inside of a structure during the winter months and minimize the amount during the summer season. Using passive energy approaches can be as simple as pulling down a window shade to block the sunlight to keep a house cooler during the summer. Active solar energy involves the collection of sunlight using solar collectors, such as metal tubes filled with water to heat the water or using photovoltaic cells to directly convert sunlight into electrical energy.

What are photovoltaic cells?

Photovoltaic cells are devices that directly change sunlight into electrical energy in the form of a direct current. Photovoltaic cells are made from semiconducting materials, such as different silicon compounds. These cells produce direct current that can be used to power a variety of devices or to recharge batteries. Improvements in photovoltaic cell technology and the mass production of these cells have lowered the cost, so more applications of the cells arise on a daily basis. If the explosion in the use of solar cells increases at the same rate as in the past, solar cells could provide all of the world's current energy needs by around the year 2050. Current photovoltaic cell energy conversion efficiency ratings only average about 20%; however, improvements are expected that will bring their efficiencies closer to 50%.

What is a solar panel?

A solar panel is a collection of solar cells arranged in a grid to collect larger amounts of sunlight than using a single photovoltaic cell. Solar panels are usually located on roofs and positioned to collect the largest amount of sunlight possible during the various seasons. A larger solar panel featuring a greater number of solar cells would collect more sunlight than a smaller panel under similar conditions.

What is insolation?

Insolation is the amount of sunlight or solar radiation that reaches a planet. Some of the radiation is absorbed or reflected by the planet's atmosphere if present and some of the radiation reaches the surface fo the planet.

What are the equinoxes?

The autumnal and vernal equinoxes are two days during the year on Earth when the sun is directly positioned above the equator. On these days, the amount of daylight and night are exactly the same number of hours.

Here are some definitions to help you in your Lessons 1 and 2 investigations.

Cardinal Directions - North, South, East, and West

Solar Panel - a device that changes sunlight into electrical energy

Energy - the ability to do work

Kilowat × hours (kWhr) - a measure of the energy converted

Seasons - four parts of the year that differ in weather and sunlight due to the tilt of Earth relative to the Sun

Spring Equinox - the day when the sun appears to cross the equator heading northward and the length of the day and night are equal

Autumnal Equinox - the day when the sun appears to cross the equator heading southward and the length of the day and night are equal

Hemisphere - one-half of a sphere

Equator - an imaginary line drawn around Earth separating the Northern and Southern Hemispheres
You need to log in to access this simulation.