Power Solutions

Introduction to Electricity and its Relation to Renewable Energy

Working with Electricity

We all deal with electricity on a daily basis with little thought of where that energy is coming from and how it is generated and we just expect our light bulb to light up when the switch is turned on. Currently, most electricity is produced using non-renewable energy producing sources. Coal, oil, and natural gas create most of the world's electricity and once the energy is captured from these sources, that energy cannot be attained again. For example, when you burn a tank of fuel in your vehicle, you need to refill it with new gasoline, diesel, etc. Now when you enter the realm of Renewable Energy, that same source can provide energy over and over again. Take solar panels. You can produce decades of power from one solar cell. This has major implications, since the world's demand for non-renewable energy has increased substantially over the last century; we need to start looking at alternate energy sources, to replace our vital non-renewable energy sources. Renewable energy will ensure that we can still produce electricity without using our important non-renewable resources that are needed in situations where alternate energy sources are not yet suitable. For example, we still need non-renewable energy to produce renewable energy products. So, if we have no non-renewable sources, we have no renewable energy sources.

Measuring Electricity

The power unit of measurement for electricity is watts, which is derived from amperage (current) multiplied by voltage. All electrical appliances we use provide a wattage measurement, which then allows you to calculate power usage under operation. Power usage over a certain period of time will either be measured in watt hours or amp hours. For simplicity's sake, we will use watt hours. For example, if want to calculate how much power you would use in 8 hours from a 100 watt light bulb, you would apply the following calculation. You take the power rating of 100 watts and multiply that by 8 hours, which would yield 800 watt/hrs. Now if you times that by 7 days, you have just used 5600 watt/hrs or 5.6 kW/hrs of power through one light bulb. It's amazing how fast it can add up.

Familiarizing yourself with basic electrical jargon

Volts: This is the electrical force behind the electrons that are flowing through electrical lines. A good analogy of this is if you refer to the common use of using a garden hose. When you turn on the tap, you can only turn on the tap slightly yielding low water pressure ( or low voltage) or can turn the tap on all the way yielding high pressure (high voltage).The higher the water pressure, the more efficiently the water travels through the hose. So basically, the higher the voltage, the more efficient the electrons will travel. Volts is derived from Ohm's Law that states:

I=E/R or and easier to remember version: E=IR
E=Volts I=Current (amps) R= Resistance

Current (amperage): this is the amount of electrons that flow past a certain point within a second. This measurement can be compared to water volume ( 1 gal/ sec.) flowing through a pipe. This measurement is also placed on electrical appliances. You can use Ohm's law to figure out current flowing through a particular conductor.

Resistance: this is the restriction of electrons in a conductor. Certain conductors offer low restriction, which would allow for a good conductor. Some elements are poor conductors, which result in high restriction. When dealing with electrical wire, wire size has an affect. For example, in situations that require large current flow, such as starting your vehicle, if your wire size is too small, the required number of electrons will not be able to flow, thus creating high resistance and very low efficiency. Ohm's law is also used to determine resistance.

Power Sizing Chart

Approximate Power Draw for Some Common Household Appliances

Well Pump: 1400 watts, Laser Printer: 400-600 watts

* VCR: 20 watts, Incandescent Lights: 15-100 watts
* 30" TV: 125 watts, Stereo: 10-30 watts
* Fridge: 250-500 watts, Microwave: 800 watts
* Coffee Maker: 600 watts, Drill: 300 watts
* Furnace Fan: 500-600 watts, Hair Dryer: 1500 watts