Portable Solar Power Glossary

Portable Solar Power

Glossary

(for terms in this blog, as well as terms you will encounter when searching for portable solar devices)

AC - See Alternating Current in this glossary

Alternating Current (AC) A type of electrical current, in which the direction of the electrical flow switches back and forth regularly (usually 60 times per second in the US, or 50 times per second in Europe). AC is the type of electricity which flows in power lines and comes is the normal household electricity which comes from a wall outlet. AC is generally needed to power larger appliances and electronic devices. A solar cell typically creates Direct Current. In order to change this current into AC, an inverter can be used. See also Direct Current, Inverter, and Cell in this glossary.

Ampere (also Amperes, Amps) A unit of electrical power. The amount of amperes of a flow of electricity indicates the rate of the flow of the electric current. Amperage is affected by the voltage of the electricity (voltage is how much electricity is available, and thus how much pressure there is on the electrical flow) and by the amount of resistance there is to the flow. (Resistance is anything which holds back the flow of the current.) See also Volt and Watt in this glossary.

To understand this better, consider the analogy of a bucket of water hanging in a tree. The bucket is full of water, but it has a small hole in the side. From this hole, water is flowing into a wading pool on the ground beneath the bucket.

The water represents the electricity. The bucket represents the source of the electricity. The amount of water in the bucket represents the volts. The hole in the bucket represents the amperage (i.e., the amount of amperes.) The amount of water which arrives into the wading pool in a certain amount of time represents the watts.

If you fill the bucket, full, to the top, with two gallons of water, it will flow out of the hole with a greater force and pressure than it would if you only filled it with two inches of water at the bottom. This represents the voltage. When an electrical current has higher voltage, it has more electricity available and pushing at the current. The flow thus has greater pressure.

If you have a small hole in the side of your bucket, the water will flow out slower than it would if you had a large hole. This hole represents the amperage. If the hole is bigger, the water will flow out faster. In an electrical current, amperage measures the speed and amount of the flow of electrical energy.

The amount of water that arrives into the wading pool in a given length of time represents the watts. In electronics, if you want to know how many watts are being generated, multiply the amperes times the volts, with this formula:

Amperes x Volts = Watts

If you have two buckets and two wading pools, consider the following analogy. One bucket is full of two gallons of water but has a small hole. The other bucket has only two inches of water but it has a large hole. The rate with which these two buckets would add water to their respective wading pools would be the same.

Similarly, in electronics, a device with 100 volts and 4 amperes would have 400 watts. A device with 200 volts and 2 amperes would also have 400 watts.

Cell A device that produces electricity. An example of an electrical cell is a flashlight battery. A solar cell uses light to produce electricity.

DC - See Direct Current in this glossary

Direct Current (DC) Electricity flowing in one direction. This is the type of electricity generated by common batteries such as flashlight batteries. It is also the type of electricity generated by solar cells. In order to change this electricity into Alternating Current (AC) the solar cell typically uses an inverter. See also Alternating Current, Inverter, and Cell in this glossary.

Inverter A device which changes electrical current from Direct Current to Alternating Current. See also Direct Current and Alternating Current in this glossary.

Photo A prefix or suffix meaning "of, from or containing light." It comes from the Greek word phos, which means "light."

Photovoltaic Creating electrical energy when exposed to light.

Solar Of or from the sun. Solar electricity is electricity which is created by the sun. Solar devices can also use light from other sources.

Voltaic Producing electric current. The word comes from the name of Alessandro Volta, an Italian physicist who was a pioneer in the field of electricity during the 1700's.

Watts The total amount of power which is generated or used by a particular device. The amount of Watts is equal to the amount of amperes multiplied by the amount of volts. See also Ampere and Volt in this glossary.

Volt A unit of measurement for electricity. It indicates how much pressure there is on an electrical current. For example, a current with 100 volts has more electricity available (and thus, more pressure on the electrical flow) than a current with 20 volts.