Solar energy is the cleanest and most abundant renewable energy source available.
Solar power is energy from the sun that is converted into thermal or electrical energy. There are several ways to harness solar energy: photovoltaic, solar heating & cooling, concentrating solar power and passive solar.
The first three are active solar systems, which use mechanical or electrical devices that convert the sun’s heat or light to another form of usable energy. Passive solar buildings are designed and oriented to collect, store, and distribute the heat energy from sunlight to maintain the comfort of the occupants without the use of moving parts or electronics.
Solar Energy Farms have been around since the 80’s. The cost for producing electricity from solar panels has been reduced dramatically as manufacturers improve on the technology. The industry is working on scaling up the production while driving the manufacturing costs down.
How does Solar power work?
Solar, or photovoltaic, cells convert sunlight directly into electricity. Most photovoltaic cells are made primarily of silicon, the material used in computer semiconductor chips, and arranged on rectangular panels. When sunlight hits a cell, the energy knocks electrons free of their atoms, allowing them to flow through the material. The resulting DC (direct current) electricity is then sent to a power inverter for conversion to AC (alternating current), which is the form in which electric power is delivered to homes and businesses.
Where is Solar Energy Used
Solar power plants are being built throughout the world. Homeowners, farms and businesses across the world are installing solar panels to reduce their electric bills. Many farms and businesses, with their open acreage and/or large buildings, can install enough solar to pay their entire electric bill, or at least reduce costly summer electricity rates.
Solar energy has been used for many years to power up exterior lights, charge laptops, etc.
Advantages of Solar Energy
- Sunlight is free and infinitely renewable.
- Unlike conventional fossil fuel and nuclear power, solar power produces no polluting emissions, including those that cause global warming.
- With no moving parts, solar panels are silent, easy to operate, and rarely need maintenance.
- Solar power can slash utility bills for both residential and commercial consumers.
- Solar panels can help utilities avoid brownouts and blackouts. When demand for electricity is high, utilities can use the panels to generate extra energy rather than fire up expensive and polluting “peak” power plants that otherwise lie dormant.
Cost of Electricity
Electricity prices vary by location due to type of power plants, cost of fuels, fuel transportation costs and state pricing regulations. The states with the highest average residential price of electricity in 2014 were:
- Hawaii (37.34¢ per kWh)
- New York (20.05¢ per kWh)
- Connecticut (19.59¢ per kWh)
Those with the lowest average prices in 2014 were:
- Washington (8.71¢ per kWh)
- North Dakota (9.25¢ per kWh)
- West Virginia (9.33¢ per kWh)
2014 residential electricity prices were highest in Hawaii, 37.34¢ per kilo-watt hour (kWh), because most of their electricity is generated using crude oil.. The lowest price was in the state of Washington with 8.71¢ per kWh.
The US average residential household used 909 kWh per month and the average monthly electricity bill was $125 before taxes and fees. Prices are higher for residential and commercial customers than industrial customers because it costs more to distribute the electricity and step the voltages down. Industrial customers use more and can take their electricity at higher voltages so it does not need to be stepped down. These factors make the price of power to industrial customers close to the wholesale price of electricity (the price from one utility to another)
How Much Solar Power Is Reasonable?
When we say that PV will eventually be at parity with natural gas and coal, that does not mean there will not be any coal or natural gas generators thereafter. Because the sun shines only during daylight hours, and wind is most prevalent at night, both are variable. We can not be totally dependent on renewables in the foreseeable future. Currently, wind provides 4% and solar less than 1% of US electricity. An electrical generation target of 20% solar and wind by 2040 seems reasonable. (For reference, 20% of US electricity is the equivalent of the energy now used in 2015 by all the cars and light trucks in the US.) The solar and wind figures could be larger if there were some “dramatic cost improvements” in grid electricity storage, notably large battery systems. However at the moment, large battery storage at the grid level looks a long ways off.
In addition, more than 20% of solar and wind would require major investments in transmission lines. Not only are transmission lines expensive, but they are hard to permit because of the NIMBY (not-in-my-back-yard) factor. Transmission lines also require three to four years to build, versus solar or wind plants which can be easily built in two years. If by 2040, 20% of our electricity comes from solar and wind, almost everyone will be happy with the situation.