Solar Energy Basics

 

What is Solar Energy?

 

Solar is the Latin word for sun - a powerful source of energy that can be used to heat, cool, and light our homes and businesses. That's because more energy from the sun falls on the earth in one hour than is used by everyone in the world in one year.  A variety of technologies convert sunlight to usable energy for buildings.  The most commonly used solar technologies for homes and businesses are solar water heating, passive solar design for space heating and cooling, and solar photovoltaics for electricity.  Solar Energy is:

 

Reliable.  As long as the sun is shining, today’s solar systems are making electricity with a 99.9% reliability.  There are no moving parts and nothing to wear out.  Most modern solar modules are backed by a 25-year manufacturer’s performance warranty and are expected to continue to provide efficient solar power well beyond that time.

Proven.  The technology for solar electrical energy is proven by over 50 years of use in many different stand-alone and grid-tied applications including, but not limited to agriculture, commercial, industrial, institutional, governmental, residential, marine, and even space exploration.

Secure.  Solar electrical energy systems provide security from rising electricity rates.  With net metering, rebates and incentives, cost savings can be substantial and ongoing.

Expandable.  Solar electrical energy systems are “modular”, and may be expanded incrementally to meet future growing electrical energy needs.

Quiet.  Solar electrical energy systems are completely silent as they produce free, clean, electricity.

Safe.  Solar electric energy systems do not require the use of combustible fuels and are safe when properly designed and installed by qualified technicians.

Simple.  Solar electric energy systems require only periodic inspection and occasional maintenance, not requiring expensive refurbishment or replacement of “consumables” common to other types of power generation.

Affordable.  Solar electric energy is produced using only free sunshine as fuel.  No other fuel source is required, and there are no costs associated with purchasing, storing or transporting fuel.

Responsible.  Solar electric energy is an environmentally responsible technology.  In today’s environmentally conscious society, people can enjoy the benefits of modern electrical conveniences without being concerned with creating environmental pollution or dangerous by-products.

Preferred.  Surveys have shown conclusively that people prefer to do business with companies that are environmentally conscious and are doing something positive to demonstrate their commitment to a clean environment.

Valuable.  Solar electric energy savings add bottom-line profits and the systems add property value without increasing property taxes.  Excess power may be sold to the utility company, and renewable energy credits from the generation of power may be traded or sold.  For example, in the PNM service area the value of net metering coupled with the solar PV produced power (REC), equals a combined value of approximately 23 cents per kilowatt hour (kwh).  When the net metering and REC payment benefits are combined with the 30% income tax credit (ITC), federal grants, and accelerated depreciation on commercial systems, the economic return of solar systems is very attractive, and solar power continues to pay for itself for years to come.

 

How Does It Work?

 

Solar Photovoltaic Technology

 

Solar cells, also called photovoltaic (PV) cells by scientists, convert sunlight directly into electricity. PV gets its name from the process of converting light (photons) to electricity (voltage), which is called the PV effect. The PV effect was discovered in 1954, when scientists at Bell Telephone discovered that silicon (an element found in sand) created an electric charge when exposed to sunlight. Soon solar cells were being used to power space satellites and smaller items like calculators and watches. Today, thousands of people power their homes and businesses with individual solar PV systems.

 

 

Solar panels used to power homes and businesses are typically made from solar cells combined into modules that hold 40-60 cells. A typical home will use about 10 to 20 solar panels to power the home. The panels are mounted at a fixed angle facing south, or they can be mounted on a tracking device that follows the sun, allowing them to capture the most sunlight. Many solar panels combined together to create one system is called a solar array. For large electric utility or industrial applications, hundreds of solar arrays are interconnected to form a large utility-scale PV system.

 

 

Traditional solar cells are made from silicon, are usually flat-plate, and generally are the most efficient. Second-generation solar cells are called thin-film solar cells because they are made from amorphous silicon or nonsilicon materials such as cadmium telluride. Thin film solar cells use layers of semiconductor materials only a few micrometers thick. Because of their flexibility, thin film solar cells can double as rooftop shingles and tiles, building facades, or the glazing for skylights.  Solar cells produce direct current (DC) power, which cannot be used in a typical installation, and it must be converted to alternating current (AC) power, using a power inverter.

                                

            Solar Panels                                              Solar Power Inverter

 

Third-generation solar cells are being made from variety of new materials besides silicon, including solar inks using conventional printing press technologies, solar dyes, and conductive plastics. Some new solar cells use plastic lenses or mirrors to concentrate sunlight onto a very small piece of high efficiency PV material. The PV material is more expensive, but because so little is needed, these systems are becoming cost effective for use by utilities and industry. However, because the lenses must be pointed at the sun, the use of concentrating collectors is limited to the sunniest parts of the country.

 

Residential Solar Power

 

 

Residential Solar Power can make a big difference in your budget and in the environment.  When you switch to solar power, you lower your electric utility bills now, and protect your family from continually rising electricity costs in the future.  Solar Power is also good for the environment.  A typical residential solar power system can save the emissions equivalent of many thousands of miles of automobile driving each year.

 

 

Commercial Solar Power

 

Businesses and industry use solar power technologies to diversify their energy sources, improve efficiency, and save money.  Commercial Solar Power offers multiple benefits. As energy costs continue to rise, profits are squeezed and the ability to remain competitive may be threatened.  Solar energy not only offers a secure future through current cost savings and future cost stabilization, but also provides the opportunity to be a leader in the green market as a company that takes a stand towards a positive impact on the community and the environment.

Solar Photovoltaic (PV) Myths and Facts

Myth: Solar power is too expensive to be practical.

Fact:

Manufacturing costs for solar panels are declining each year through new research and economies of scale.  The cost of an installed solar PV system has decreased by about 30% over the past 10 years.

Once a solar PV system is purchased and installed, solar power costs nothing and, through net metering, can actually create a positive cash flow from the sale of excess power and RECs.

Government rebates and grants and utility company incentives can decrease the up-front cost of a solar PV system by as much as 50% or more.

Myth: PV systems are ugly and unreliable.

Fact:

Solar panels on homes are typically installed using low-profile mounting brackets. The sleek panels are placed almost flush against the roof. Roof-integrated solar shingles are available as well.

Many buildings now have solar power systems integrated into their designs.  Older buildings may be retrofitted or ground mount systems may be used.

PV systems are known for their dependability; warranties are typically 20+ years and, as there are no moving parts, no regular maintenance is required.

Myth: It takes more energy to produce a solar panel than that panel will generate in its lifetime.

Fact:

A solar panel will generate a minimum of four times the amount of energy used in its production. Soon, panels will be generating 20 times the energy required for their production.

As no fuel is needed to make power, a solar PV system consumes no energy and produces no harmful pollutants or dangerous by-products.

A typical home-sized PV system saves the pollution equivalent and the energy used for 625,000 miles of automobile driving over 20 years.

Myth: Solar PV power is a nice idea, but it will never compete with conventional fuels.

Fact:

The solar energy industry is currently growing at a rate of 25 percent each year.

At the current consumption rate, fossil fuels may be depleted within 40 years; at best, they will be more expensive and continue to harm the environment.  Solar PV power solves both of these problems.

The price of fossil fuels continues to increase each year and will escalate faster as supplies dwindle.

Solar energy is the fastest growing energy technology in the world, and the price of solar PV systems using that technology is decreasing.