Water Heaters

Posts Tagged ‘coal’

Solar Water Heater

Solar Water Heaters

Solar water heaters can be a cost-effective way to generate hot water for your home. They can be used in any climate, and the fuel they use (sunshine) is free.

solar water heating

Solar water heating is water heated by the use of solar energy. Solar heating systems are generally composed of solar thermal collectors, a water storage tank or another point of usage, interconnecting pipes and a fluid system to move the heat from the collector to the tank. This thermodynamic approach is distinct from semiconductor photovoltaic (PV) cells that generate electricity from light; solar water heating deals with the direct heating of liquids by the sun where no electricity is directly generated. A solar water heating system may use electricity for pumping the fluid, and have a reservoir or tank for heat storage and subsequent use. The water can be heated for a wide variety of uses, including home, business and industrial uses. Heating swimming pools, under floor heating or energy input for space heating or cooling are common examples of solar water heating. A solar water heating system can form part of a solar thermal cooling system, promoting efficient temperature control of buildings or parts thereof. During cool conditions, the same system can provide hot water.

solar water heater

In order to heat water using solar energy, a collector, often fastened to a roof or a wall facing the sun, heats working fluid that is either pumped (active system) or driven by natural convection (passive system) through it. The collector could be made of a simple glass topped insulated box with a flat solar absorber made of sheet metal attached to copper pipes and painted black, or a set of metal tubes surrounded by an evacuated (near vacuum) glass cylinder. In industrial cases a parabolic mirror can concentrate sunlight on the tube. Heat is stored in a hot water storage tank. The volume of this tank needs to be larger with solar heating systems in order to allow for bad weather, and because the optimum final temperature for the solar collector is lower than a typical immersion or combustion heater. The heat transfer fluid (HTF) for the absorber may be the hot water from the tank, but more commonly (at least in active systems) is a separate loop of fluid containing anti-freeze and a corrosion inhibitor, which delivers heat to the tank through a heat exchanger (commonly a coil of copper tubing within the tank).

Residential solar thermal installations fall into two groups: passive (sometimes called “compact”) and active (sometimes called “pumped”) systems. Both typically include an auxiliary energy source (electric heating element or connection to a gas or fuel oil central heating system) that is activated when the water in the tank falls below a minimum temperature setting such as 55°C. Hence, hot water is always available. The combination of solar water heating and using the back-up heat from a wood stove chimney to heat water can enable a hot water system to work all year round in cooler climates, without the supplemental heat requirement of a solar water heating system being met with fossil fuels or electricity.

Passive solar water heating systems are typically less expensive than active systems, but they’re usually not as efficient. However, passive systems can be more reliable and may last longer.

There are two basic types of passive systems:

Integral collector-storage passive systems

These work best in areas where temperatures rarely fall below freezing. They also work well in households with significant daytime and evening hot water needs.

Thermosyphon systems

Water flows through the system when warm water rises as cooler water sinks. The collector must be installed below the storage tank so that warm water will rise into the tank. These systems are reliable, but contractors must pay careful attention to the roof design because of the heavy storage tank. They are usually more expensive than integral collector-storage passive systems.

There are two types of active solar water heating systems:

Direct circulation systems

Pumps circulate household water through the collectors and into the home. They work well in climates where it rarely freezes.

Indirect circulation systems

Pumps circulate a non-freezing, heat-transfer fluid through the collectors and a heat exchanger. This heats the water that then flows into the home. They are popular in climates prone to freezing temperatures.

Other Considerations

Solar water heating systems almost always require a backup system for cloudy days and times of increased demand. Conventional storage water heaters usually provide backup and may already be part of the solar system package. A backup system may also be part of the solar collector, such as rooftop tanks with thermosyphon systems. Since an integral-collector storage system already stores hot water in addition to collecting solar heat, it may be packaged with a demand (tankless or instantaneous) water heater for backup.

When a solar water heating and hot-water central heating system are used in conjunction, solar heat will either be concentrated in a pre-heating tank that feeds into the tank heated by the central heating, or the solar heat exchanger will replace the lower heating element and the upper element will remain in place to provide for any heating that solar cannot provide. However, the primary need for central heating is at night and in winter when solar gain is lower. Therefore, solar water heating for washing and bathing is often a better application than central heating because supply and demand are better matched. In many climates, a solar hot water system can provide up to 85% of domestic hot water energy. This can include domestic non-electric concentrating solar thermal systems. In many northern European countries, combined hot water and space heating systems are used to provide 15 to 25% of home heating energy.

Selecting a Solar Water Heater

Before you purchase and install a solar water heating system, you want to consider the following:

The Economics of a Solar Water Heater

Solar water heating systems usually cost more to purchase and install than conventional water heating systems. However, a solar water heater can usually save you money in the long run.

How much money you save depends on the following:

  • The amount of hot water you use
  • Your system’s performance
  • Your geographic location and solar resource
  • Available financing and incentives
  • The cost of conventional fuels (natural gas, oil, and electricity)
  • The cost of the fuel you use for your backup water heating system, if you have one.

On average, if you install a solar water heater, your water heating bills should drop 50%–80%. Also, because the sun is free, you’re protected from future fuel shortages and price hikes.

If you’re building a new home or refinancing, the economics are even more attractive. Including the price of a solar water heater in a new 30-year mortgage usually amounts to between $13 and $20 per month. The federal income tax deduction for mortgage interest attributable to the solar system reduces that by about $3–$5 per month. So if your fuel savings are more than $15 per month, the solar investment is profitable immediately. On a monthly basis, you’re saving more than you’re paying.

Evaluating Your Site’s Solar Resource for Solar Water Heating

Before you buy and install a solar water heating system, you need to first consider your site’s solar resource. The efficiency and design of a solar water heating system depends on how much of the sun’s energy reaches your building site.

Solar water heating systems use both direct and diffuse solar radiation. Even if you don’t live in a climate that’s warm and sunny most of the time—like the southwestern United States—your site still might have an adequate solar resource. If your building site has unshaded areas and generally faces south, it’s a good candidate for a solar water heating system.

Your local solar system supplier or installer can perform a solar site analysis.

Sizing a Solar Water Heating System

Sizing your solar water heating system basically involves determining the total collector area and the storage volume you’ll need to meet 90%–100% of your household’s hot water needs during the summer. Solar system contractors use worksheets and computer programs to help determine system requirements and collector sizing.

Collector Area

Contractors usually follow a guideline of around 20 square feet (2 square meters) of collector area for each of the first two family members. For every additional person, add 8 square feet (0.7 square meters) if you live in the U.S. Sun Belt area or 12–14 square feet if you live in the northern United States.

Storage Volume

A small (50- to 60-gallon) storage tank is usually sufficient for one to two three people. A medium (80-gallon) storage tank works well for three to four people. A large tank is appropriate for four to six people.

For active systems, the size of the solar storage tank increases with the size of the collector—typically 1.5 gallons per square foot of collector. This helps prevent the system from overheating when the demand for hot water is low. In very warm, sunny climates, some experts suggest that the ratio should be increased to as much as 2 gallons of storage to 1 square foot of collector area.

Solar Water Heater Energy Efficiency

For a solar water heating system, use the solar energy factor (SEF) and solar fraction (SF) to determine its energy efficiency.

The solar energy factor is defined as the energy delivered by the system divided by the electrical or gas energy put into the system. The higher the number, the more energy efficient. Solar energy factors range from 1.0 to 11. Systems with solar energy factors of 2 or 3 are the most common.

Another solar water heater performance metric is the solar fraction. The solar fraction is the portion of the total conventional hot water heating load (delivered energy and tank standby losses). The higher the solar fraction, the greater the solar contribution to water heating, which reduces the energy required by the backup water heater. The solar fraction varies from 0 to 1.0. Typical solar factors are 0.5–0.75.

Estimating a Solar Water Heater System’s Cost

Before purchasing a solar water heating system, you can estimate its annual operating cost and compare it with other more and/or less efficient systems. This will help you determine the energy savings and payback period of investing in a more energy-efficient system, which will probably have a higher purchase price.

Calculating Annual Operating Cost

To estimate the annual operating cost of a solar water heating system, you need the following:

  • The system’s solar energy factor (SEF)
  • The auxiliary tank fuel type (gas or electric) and costs (your local utility can provide current rates).

Then, use the following calculations.

With a gas auxiliary tank system:

You need to know the unit cost of fuel by Btu (British thermal unit) or therm. (1 therm = 100,000 Btu)

365 × 41,045/SEF × Fuel Cost (Btu) = estimated annual cost of operation


365 × 0.4105/SEF × Fuel Cost (therm) = estimated annual operating cost

Example: Assuming the SEF is 1.1 and the gas costs $1.10/therm

365 × 0.4105/1.1 × $1.10 = $149.83

With an electric auxiliary tank system:

You need to know or convert the unit cost of electricity by kilowatt-hour (kWh).

365 × 12.03/SEF × Electricity Cost (kWh)= estimated annual operating cost

Example: Assuming the SEF is 2.0 and the electricity costs $0.08/kWh

365 X 12.03/2.0 X $0.08 = $175.64

Building Codes, Covenants, and Regulations for Solar Water Heating Systems

Before installing a solar water heating system, you should investigate local building codes, zoning ordinances, and subdivision covenants, as well as any special regulations pertaining to the site. You will probably need a building permit to install a solar energy system onto an existing building.

Not every community or municipality initially welcomes residential renewable energy installations. Although this is often due to ignorance or the comparative novelty of renewable energy systems, you must comply with existing building and permit procedures to install your system.

The matter of building code and zoning compliance for a solar system installation is typically a local issue. Even if a statewide building code is in effect, your city, county, or parish usually enforces it locally. Common problems homeowners have encountered with building codes include the following:

  • Exceeding roof load
  • Unacceptable heat exchangers
  • Improper wiring
  • Unlawful tampering with potable water supplies.

Potential zoning issues include the following:

  • Obstructing side yards
  • Erecting unlawful protrusions on roofs
  • Sitting the system too close to streets or lot boundaries.

Special area regulations—such as local community, subdivision, or homeowner’s association covenants—also demand compliance. These covenants, historic district regulations, and flood-plain provisions can easily be overlooked.

To find out what’s needed for local compliance, contact the following:

  • Your local jurisdiction’s zoning and building enforcement divisions
  • Briefly describe your intended construction, asking for other relevant ordinances/codes that might be in effect.
  • Find out if there are any additional local amendments or modifications to the regulations in effect.
  • Ask how to determine whether you are located in a historic district, flood-plain area, or any other special category regulated by a government body.
  • Ask where you may find pertinent ordinances/codes (local library, government office, etc.).
  • Read pertinent sections of the regulations, making photocopies of information you wish to file for future review and design/installation analysis.
  • Ask if they have any ordinances, provisions, or covenants that may affect the design and installation of the system.
  • Copy and file pertinent sections for reference.
  • Homeowner’s, subdivision, neighborhood, and/or community association(s)

Installing and Maintaining the System

The proper installation of solar water heaters depends on many factors. These factors include solar resource, climate, local building code requirements, and safety issues; therefore, it’s best to have a qualified, solar thermal systems contractor install your system.

After installation, properly maintaining your system will keep it running smoothly. Passive systems don’t require much maintenance. For active systems, discuss the maintenance requirements with your system provider, and consult the system’s owner’s manual. Plumbing and other conventional water heating components require the same maintenance as conventional systems. Glazing may need to be cleaned in dry climates where rainwater doesn’t provide a natural rinse.

Regular maintenance on simple systems can be as infrequent as every 3–5 years, preferably by a solar contractor. Systems with electrical components usually require a replacement part or two after 10 years.

When screening potential contractors for installation and/or maintenance, ask the following questions:

  • Does your company have experience installing and maintaining solar water heating systems?
    Choose a company that has experience installing the type of system you want and servicing the applications you select.
  • How many years of experience does your company have with solar heating installation and maintenance?
    The more experience the better. Request a list of past customers who can provide references.
  • Is your company licensed or certified?
    Having a valid plumber’s and/or solar contractor’s license is required in some states. Contact your city and county for more information. Confirm licensing with your state’s contractor licensing board. The licensing board can also tell you about any complaints against state-licensed contractors.

Searched Solar Info

Solar Energy History

The History of Solar Energy

A History over two thousand years old, solar energy has been a part of human life for a long time. Man has used solar power in its passive form to dry food and clothing and to warm homes for most of our history. The sun is the most potent and plentiful form of physical energy in our immediate existence. Of all the forces in the Universe the star is by far the most captivating and powerful. Our own star the “Sun” may be small by Universal standards but it is a giant star by our standards. So large that it accounts for over 99% of our solar systems mass and it’s power can be felt far past our own Earth orbit.

In just 40 minutes the amount of solar energy the sun emits that strikes the earth has the potential to power every electric outlet on the planet… for a year! Understanding the facts about our sun is a great way to understand solar energy. And understanding the history of solar energy development is a good place to begin. I hope you find the following informative and entertaining!

Humans learned how to harness solar energy in more sophisticated ways around 700 BC. Here’s the Solar Energy History timeline.

7th Century B.C.

Around 700 B.C. it was learned that a beam of sunshine targeted through a piece of glass could create enough heat energy to start a fire if the ray were focused onto something flammable.

3rd Century B.C.

By third century B.C., the Greeks and Romans were reflecting the sun’s rays from mirrors to ignite ceremony torches.

2nd Century B.C.

In the 2nd century BC, Archimedes, using copper shields, reflected a beam of sun onto an enemy wooden warship in the harbor and set it ablaze. Whether the story is true or false it has since been proved that it can indeed be done with the materials of that era.

For the next 1000 years man was contented to employ the power of the sun for the intentions of starting fires, passively heating abodes and drying out food and hides.

Over these early years in Solar Energy History, cultures learned to orient their dwellings and communities to face the sun (south) and exact fullest advantage of it’s heating energy. The low hanging sun would warm up the adobe brick or stone face of the building in winter and radiate it’s heat into the domicile well into the evening.

1st to 4th Century A.D.

1st to 4th Century Romans used passive solar to heat bathhouses. Glass windows facing the south allowed the sun’s rays to penetrate and warm the bathhouse, and then prevented it from escaping.

6th Century A.D.

Passive solar heating was becoming better understood and for the next several hundred years sun-rooms appeared on the south side of many Roman homes. The heat collected in the glass sun-room was allowed in to warm the home when the doors between the sun-room and home were opened.

1050 to 1300 A.D.

Around 1050 AD to 1300 is the period of the Anasazi cliff dwellings. Built in South facing cliffs with natural stone overhangs these communities were warmed in winter by the low hanging sun but the stone overhang provided much needed shade on hot summer days.


1767 saw the first major solar discovery since the beginnings of solar energy harnessing.

Swiss scientist Horace de Saussure, in the mid 1700′s, fashioned the world’s first solar cooker.

Using a wooden box with a black cork bottom and placing three separate sheets of glass over it and finally insulating it, he was able to maintain an internal temperature of 230 degrees Fahrenheit. Hot enough to boil water and cook a meal!

Solar cookers of today closely resemble Saussure’s invention.


By the 1800′s, discoveries were being made much faster. By the latter part of the century as little as three years would pass between discoveries.

Edmond Becquerel a French Scientist discovered the photovoltaic effect in 1839. He was the first to discover that light intensified the amount of electricity generated between two electrodes. His findings were considered interesting, but were not pursued.

From 1860′s to 1880′s

the first solar powered engines were produced and put to use.
Auguste Mouchout was the first man to patent a design for a motor running on solar energy. Receiving funds from the French monarch, he designed a device that turned solar energy into mechanical steam power and soon operated the first steam engine. He later connected the steam engine to a refrigeration device, illustrating that the sun’s rays can be utilized to make ice! He was awarded a medal for this.

His groundbreaking research was cut short though. The French renegotiated a cheaper deal with England for the supply of coal and improved their transportation system for the delivery thereof. Mouchout’s work towards finding an alternative was no longer considered a priority and he no longer received any funding from the monarch.


Willoughby Smith experimented with the use of selenium solar cells after discovering it’s sensitivity to light while testing material for underwater telegraph cables.


William Adams wrote the first book about Solar Energy called: A Substitute for Fuel in Tropical Countries. He and his student Richard Day experimented with the use of mirrors and were able to power a 2.5 horsepower steam engine. His design, know as the Power Tower concept, is still in use today.


An American inventor Charles Fritz turned the sun’s rays into electricity. His selenium solar cell had a conversion rate of only 1-2%. But was another huge milestone in solar energy history!


Charles Tellier, a Frenchman who is known as the father of refrigeration, experimented with a non-concentrating/ non-reflecting solar motor. He installed the first solar energy system for heating household water on top of his own roof. However, his desire to pursue his refrigeration interests led to him to abandon all solar energy experiments.


John Ericsson, an American immigrant from Sweden wrote these powerful words: “A couple of thousand years dropped in the ocean of time will completely exhaust the coal fields of Europe, unless, in the meantime, the heat of the sun be employed.” He dismissed Mouchout’s work and also developed a solar powered steam engine, very similar in design to Mouchout’s.


History saw the first commercial solar water heater patented by Clarence Kemp an inventor from Baltimore.


Aubrey Eneas formed the first Solar Energy Company – The Solar Motor Co. They sold the first Solar Energy system to Dr. A.J. Chandler of Mesa, Ariz for $2,160. It was destroyed less than a week later by a windstorm. They sold a second one to John May, but that one too, was destroyed by a hailstorm shortly afterwards. This led to the company’s downfall.


Henry Willsie recognized the need to store generated power and built 2 huge plants in California. He was the first to successfully use power at night after generating it during the day. Even so, he was not able to make a sale and his company too folded.

1906 – 1914

Frank Shuman’s company, Sun Power Co, built the largest and most cost-effective solar energy system covering 10,000 square feet plus. Although it produced a lot of steam it did not produce enough pressure. Together with E.P. Haines he then formed Sun Power Co. Ltd. They built an irrigation plant just outside of Cairo, but unfortunately it was destroyed during the Great War.


Calvin Fuller, Gerald Pearson and Daryl Chaplin of Bell Laboratories accidentally discovered the use of silicon as a semi-conductor, which led to the construction of a solar panel with an efficiency rate of 6%.


The first commercial solar cell was made available to the public at a very expensive $300 per watt.

1950s – 1960s

Space programs employed solar technologies. In 1958 the Vanguard I was launched. The first satellite to use solar energy.


The Energy Crisis ! (OPEC oil embargo). A bit of solar energy history we are all familiar with. Suddenly it became important to find an alternative form of energy as we realized just how reliant we really are on non-renewable, finite resources like coal, oil and gas for our existence.

Solar energy history was made as the price of solar cells dropped dramatically to about $20 per watt.

1980 – 1991

A Los Angeles based company called Luz Co. produced 95% of the world’s solar-based electricity. They were forced to shut their doors after investors withdrew from the project as the price of non-renewable fossil fuels declined and the future of state and federal incentives was not likely.

The chairman of the board said it best: “The failure of the world’s largest solar electric company was not due to technological or business judgment failures but rather to failures of government regulatory bodies to recognize the economic and environmental benefits of solar thermal generating plants.”


There is a renewed focus as more and more people see the advantages of solar energy and as it becomes more efficient and more affordable.

Governments across the world offer financial assistance and incentives.

Solar electric systems are now used to power many homes, businesses, getaways, and even villages in Africa.

We see solar cells powering anything from household appliances to cars.

Solar power as a movement is gaining popularity among the people as awareness of it’s great benefit to us is being spread.

Solar Power Cost


How Much Your Residential Solar Power Will Cost

The cost of solar power for your home will depend on a number of different things. Where you live, how much power your household uses, whether you buy the panels new or used, how much sun your property receives, incentive programs available to you… etc, will all have an impact on the cost of solar power at any given location.

So just how much will it cost? Well a better question we should be asking ourselves is… What will it cost us if we do not invest in Solar Power? With the effects of Global Warming, pollution from fuels, and waste generated from power plants, we are effectively killing our most precious resource. If we do not begin to change the way we generate and use energy, we will no longer have a habitable earth to live on. We will be handing down a dead planet unable to sustain life to our children, where there will be no clean water to drink, no fresh air to breathe, or nutritious food to eat. It is time to join a movement that is for the prosperity of us all. A movement that needs your help, and all you need to do for it is save money while saving the earth.

The cost for residential solar energy generation varies greatly depending on several factors. Lets take a look at a few of them.

1. How much electricity do you need?

This should is the first question you need to ask yourself. Do you want to go 100% solar, or maybe you will want an integrated system that ties into the electrical grid to replace some of your electricity needs. The first step is to figure out how much electricity you use. Looking at your utility bill can do this. KWh or kilowatt-hour represents the usage of electricity. 1 Kilowatt-hour is equal to 1000 watts of electricity used in one hour. Lets use this example bill to show you how it is calculated.

This bill’s total kWh for the month is 460. So lets divide that by 30 to get a daily representation that will equate to 15.3 kWh a day of electrical usage. Now to get the wattage we need per day from our Solar Panels we will multiply our daily kWh by 1000 which gives us 15300 watts of usage a day.

460 kWh x .3 = 15.3 kWh x 1000 watts = 15,000 watts

Now that we have the total watts of electricity we need to generate a day we can work on the next factor.


2. How much sunshine do you get at your location?

This is actually easier then it sounds NASA has created the NASA Surface Meteorology and Solar Energy site which will be able to give you all the information you need for this next step.
For the solar panel estimator select the Insolation Average, Min and Max, and the Radiation on Equator-pointed Tilted Surface parameters. Note the yearly average figures you find for your location. Insolation means the number of hours in a day that a solar panel will produce its rated voltage.

3. You will also need to know what size, or wattage of panels you wish to use.

Keep in mind when picking out panels that you’ll want to only use the same type and size. It is fact that panels with different electrical characteristics do not work together very well. There are many types and sizes what you want is really up to you. So just for this example we’ll go with a 175-watt solar panel. Note that a higher wattage does not mean the solar panel is of better quality.

4. Now you will have to adjust for inefficiencies in your system.
What I mean by this is that when we talk about energy coming through a system, we mean that energy courses through different devices in a chain IE: charge controller, inverter, batteries. Every step of the way loses us some energy, so we want to only put things in the chain that are absolutely necessary and are in good working order. There will always be some loss to the output level. It’s just the way it works. The only thing we can really do about it is to make sure our system is as efficient as possible. If you are thinking about buying a manufactured system this information should be available from them, otherwise figure between 50% – 70% efficiency. I’ll average for example and use an efficiency of 60%.

You may have noticed when you looked at the NASA site that insolation values can go up drastically for tilted panels, or positioning panels to face towards the sun. Because of this your annual average of Insolation can almost triple. So lets use a tilt of 45 degrees in our example.

So if we went for horizontal positioned panels we would need 39 panels at 175 watts each.

If we went with the 45-degree angle we would need 34 panels at 175 watts each.

Now you can shop around for better prices but the 175-watt panels we are using for this example are $580.00 each.

Horizontal: 39 x 580 = $22,620 USD.

45 Degree angle: 34 x 580 = $19,720 USD.

I realize this seems like a large up front investment however you are adding value to your house, also making it up with non existent energy bills, selling energy back to the utility company’s, and last but not least getting tax breaks and other incentives from the government. While buying manufactured panels and having them installed may be the easiest way to get solar energy flowing through your home, it is also by far the most expensive Solar power Cost.

Solar Power Information Solar Panel Cost

The solar revolution has been happening for the last 20 years and is now really moving fast. It has taken a long time for the technology to become affordable enough for everyday people to utilize. The best part is the technology is increasing at a rapid speed. Solar panels or photovoltaic cells as they are sometimes called (photo = light, voltaic = electricity) are what’s used to generate solar power from our Sun.

Unfortunately not much energy is created by one single solar cell, which means that lots of them are needed, drastically raising solar power cost. The biggest problem with solar power is in the price you must pay to buy systems and have them installed.

There are so many reasons to install solar power into your home that it makes no sense not to anymore. More and more benefits are being discovered everyday. The solar power cost of a residential home is dramatically reduced due to the fact that after the initial investment of installing solar panels, the energy created is 100% free. Older methods of energy creation that pollute the atmosphere like coal and nuclear technology are rising in price and will continue to do so for the foreseeable future. You can even sell the solar energy to the utility company’s making you extra income. And with the benefit of the positive effects on the earth that comes with not needing to use negative forms of generating energy, you can feel good about what you’re doing. Solar panels are 100% environmentally friendly, no pollution at all!

Fortunately we are able to utilize solar power in easier and cheaper ways due to advancements in technology and techniques used to create more energy efficient, cheaper, and better looking solar panels. Luckily there are extremely easy ways to lower Solar Power Cost, and also have some fun by making your own solar panels. Doing it yourself can drastically lower the amount of money you’ll spend on your initial investment. I highly recommend trying it out, but be careful when purchasing a kit, they are not all perfect for any situation. You need to make sure you get what is right for you. If you would like more detailed information please visit Solar Power Cost to check out a kit I have used myself and know first hand that it works perfect in any situation.

The Bottom Line

You can reasonably expect to power your home completely with solar power, for $25,000 US dollars including the cost of new batteries. Once installed the system will save you ALL of your power expense for 35 to 40 years.

It may take a while but after a period of 10 to 15 years, the system will have paid for itself (in energy savings) and then it begins to put money back into your pocket for as long as 20 more years. And this is without any subsidies or tax incentives, or taking into account any parts you built or installed yourself. If you do most of the work yourself and take advantage of all the incentives and breaks you are looking at an investment below $10,000 USD.

So in closing thank you for visiting our Solar Power Cost page. New content and more Solar Energy Facts will be published regularly so please visit often, tell your friends, and bookmark us. Also if you would like to join the RSS feed and receive automatic updates whenever a new post is added click on the RSS icon at the bottom left corner of the page.

Solar Energy Facts


General facts

  • Solar Energy production is better for the environment than conventional forms of energy production.
  • Solar energy has many uses other than electricity production. For instance heating of water with solar thermal energy, water treatment through solar distillation and chemical production through solar reaction.
  • Solar energy can be used to heat swimming pools, power cars, power phones, radios and other small appliances.
  • You can cook food with solar energy.
  • Solar Energy is becoming more popular each day. The world demand for Solar Energy is currently greater than the supply.

Facts about Solar Energy usage:

  • Solar Energy is measured in kilowatt-hour. 1 kilowatt = 1000 watts.
  • 1 kilowatt-hour (kWh) = the amount of electricity required to power a 100 watt light bulb for 10 hours.
  • According to the US Department of Energy, an average American household used approximately 888-kilowatt hours per month in 2009 costing them $94.26.
  • About 30% of our total energy consumption is used to heat water.

Facts about Solar Energy systems:

  • A typical home solar system is made up of solar panels, an inverter, a battery, a charge controller, wiring and support structure.
  • A 1-kilowatt home solar system takes about 1-2 days to install and costs around $10,000 USD, but can vary greatly and does not take into account any incentives offered by the government.
  • A 1-kilowatt home solar system consists of about 10-12 solar panels and requires about 100 square feet of installation area.
  • A 1-kilowatt home solar system will generate approximately 1,600 kilowatt hours per year in a sunny climate (receiving 5.5 hours of sunshine per day) and approximately 750 kilowatt hours per year in a cloudy climate (receiving 2.5 hours of sunshine per day).
  • A 1-kilowatt home solar system will prevent approximately 170 lbs. of coal from being burned, 300 lbs of CO2 from being released into the atmosphere and 105 gallons of water from being consumed each month!
  • About 40 solar cells are usually combined into a solar panel and around 10-12 panels mounted in an array facing due North to receive maximum sunlight.
  • An average solar system usually comes with a 5-year warranty, although the solar panels are warranted for 20.
  • Relying on the battery back up, a solar energy system can provide electricity 24×7, even on cloudy days and at night.
  • Solar panels come in various colors.
  • Solar energy can be collected and stored in batteries, reflected, insulated, absorbed and transmitted.

Sun related Facts about Solar Energy:

  • Sunlight travels to the earth in approximately 8 minutes from 93,000,000 miles away, at 671,000,000 miles per hour.
  • Our sun is also the main source of non-renewable fossil fuels (coal, gas and petroleum), their energy was originally converted from sunlight by photosynthesis over millions of years.
  • Solar energy is responsible for weather patterns and ocean currents.
  • Clouds, pollution and wind can prevent the sun’s rays from reaching the earth.
  • The sun accounts for about 99.86% of the total mass of our Solar System.
  • Sunlight on the surface of the Earth is attenuated by the Earth’s atmosphere so we receive only 1,000 watts per square meter of its power in clear conditions.

Other Interesting Facts about Solar Energy:

  • In one hour more sunlight falls on the earth than what is used by the entire population in one year.
  • A world record was set in 1990 when a solar powered aircraft flew 2522 miles across the United States, using no fuel.
  • Fierce weather cost the world a record $130 Billion in the first eleven months of 1998- more money than was lost from weather related disasters from 1980 to 1990 ($82 Billion).
  • Researchers from the Worldwatch Institute and Munich Re blame deforestation and climate change from Earth warming for much of the loss. The previous one-year record was $90 Billion in 1996. Source – Associated Press, November 28,1998.
  • About 2 billion people in the world are currently without electricity.
  • Accounting for only 5 percent of the world’s population, Americans consume 26 percent of the world’s energy.
  • Electric ovens consume the most amount of electricity, followed by microwaves and central air conditioning.
  • Third world countries with an abundance of sunlight and a population currently without electricity, represents the fastest growing market for solar energy, with the largest domestic market being the utilities sector.
  • Shell Oil predicts that 50% of the world’s energy will come from renewable sources by 2040.

Morocco’s new Solar Project to Generate 2000MWs

Morocco is a North African country without any oil reserves. But nature has blessed this country with another bounty i.e. over 3000 hours of sunlight annually. Now they are taking aim to undertake an ambitious plan of developing 40% of their energy needs via solar energy. They’ll spend $9 billion to generate 2000MWs of energy by 2020. It will require 5 solar power stations to create 2000MWs of energy. These power stations will be located in the regions of Ouarzazate, Ain Bni Mathar, Foum Al Oued, Boujdour and Sebkhat Tah. The first station is anticipated to become operational by 2015.

Morocco’s Finance Minister Salaheddine Mezouar wants the world to perceive Morocco as an environmentally friendly country. He said, “The project sends a very clear message in the current situation, which is dominated by the need to face up to the challenges of climate change.” The minister added that “Morocco is determined to protect the environment in all its future projects.”

Morocco’s authorities are confident of the success of this project. Energy Minister Amina Benkhadra makes a promise, “This is a bold but realistic project. We will guarantee all the technical and financial resources to make it succeed.”

This country’s politicians are anxious to cut its dependence of foreign oil and gas imports and save money and to leave green footprints in the sands of time. For the project, Morocco is mobilizing multiple financing sources and partners. Morocco can get assistance for this project from the World Bank, the European Commission, and Germany and Desertec. Desertec is a coalition of 13 energy and engineering companies aiming for a renewable energy grid in Africa and subsequently shipping the energy to Europe. Desertec was founded in 2009. Their organization’s focus is on alternative power generation using wind and sunlight. They would like to build a series of concentrated solar power (CSP), photovoltaic (PV) and wind projects in the Middle East and North Africa region.

Said Mouline is the director of Morocco’s Centre for Renewable Energy Development. He says, “This project will help Morocco reduce its greenhouse gas emissions by 3.7 million tonnes of CO2. This will help us play our role in mitigation of climate change.” He said again, “Clean energy projects such as this will create many new jobs in the areas selected for the solar plants as well as boost the country’s scientific expertise in the field of solar energy.”

Now the Arab countries are waking up to the reality of oil reserves. They also want to trap the power of alternative sources of energy. Algeria, Qatar, Tunisia and Saudi Arabia, Jordan, Syria and Tunisia are all making fruitful attempts to utilize the power of sunlight. Israel is already using solar power with success in many areas such as water heating systems. Israel is also earning reputation as a global leader in innovating solar energy solutions. Morocco might seek help of Israel on this ambitious project as well.

The Energy Minister stressed that they will use the state-of-the-art technology available in the market. She says, “We look for the most sophisticated technology available in the world to use for this project.”

Ali Fassi Fihri is the Chairman of ONE, Morocco’s power utility. He shares his opinion, “The project would add in terms of power generation the equivalent of the current electricity consumption of the country’s commercial capital Casablanca.”

China Unveils World’s Largest Solar Office Building

China is frequently dubbed as a heavy user of fossil fuels and polluter or a climate killer. Because it meets the 70% of its power demands by exploiting coals. But they are making alterations on the environment front as well. Slowly and steadily they are selecting wind and solar power as their source of energy. China has earned the distinction of having the world’s largest solar-powered building. It’s located in Dezhou, Shangdong Province in northwest China. The building covers an area of 75,000-square-meter. The office building is modelled after the sun dial structure.

The building supplies many services such as space for exhibition centers, scientific research facilities, meeting and training facilities and a sustainable hotel. This building is referred as the Sun and the Moon Altar micro-row buildings. The architecture included the Chinese characters for sun and moon. The solar building has a white exterior that represents clean energy.

The clean and green ideas are not confined to the massive solar array entirely but can be spotted in the whole building complex. They’ve utilized only 1% of steel to the Bird’s nest. Their advanced roof and wall insulation system consume 30% less energy than the national energy saving standard. The building will be showcased to the whole world during the 4th World Solar City Congress. The building’s pioneering solar energy and power-saving technologies, a few already patented, include a number of technical advancements that will push forward the mass application of solar energy.

The building will secure 95% of its energy needs from alternative energy sources. They have established a 5000 square meter solar panel array on the building complex. This building as well has the facilities of solar hot water, a solar desalination plant and a solar energy theme park.

Dezhou could safely be termed as a solar city because among 5.5 million people existing in this city most of them opted for the solar hot water systems. In this city, solar energy is all pervasive. It powers everything from street lighting to tourist cars.

Greenpeace put forth a lot of statistics for this city. According to them, in 2007, 800,000 people in Dezhou had jobs in the solar panel industry. Greenpeace anticipates that this figure is anticipated to grow to 1,500,000 by 2020.

Cheap Energy with New Solar Device

Researchers and scientists are putting on continuous attempt to make the sources of energy clean and green. There are many devices in the market that run on solar energy. The alternative energy atmosphere is charged with anticipation and excitement. But until now one of the biggest dampeners in green energy scenario is the costs. Fossil fuels are available inexpensively all over the globe. But solar, wind, geothermal or biofuels are still expensive and out of reach of commoners.

The University of Arizona’s Steward Observatory Mirror Lab has paid attention to this particular aspect. They have created the first prototype of a solar device that will hopefully not be outrageously priced. The device’s inventor Roger Angel’s prospects will ultimately generate electricity from the sun at a price similar to the cheapest fossil fuels. That is what manufacturer and consumer both want. Every manufacturer aims for profit and all end users want to save money.

Roger Angel’s prototype makes use of mirrors. These mirrors are set up in such a way that 21 segments form an array in a parabola on a lightweight aluminum frame. This arrangement helps in focusing the sun’s light on a small solar cell. Its first prototype is supposed to be shipped next week to Raytheon Missile Systems. This design could be used to build portable solar generators for battlefield deployment. This fact is reveled by Eric Betterton. He is a UA professor of atmospheric sciences and he is also the principal investigator for the project.

The prototype costs approximately about $300,000 to engineer and put together, with its mirrors forged one by one in the mirror lab and hand-coated. This project is undertaken by the UA with grants from Science Foundation Arizona. Angel who is the Mirror Lab’s founder and director, said the device uses only about $200 worth of glass and ultimately could be mass-produced for $1,500. It is estimated that at that price, the device would create energy for $1 a watt. This is as cheap as coal-burning electrical plants.

Ontario buys Solar Electricity from Homeowners

Homeowners who buy and install home solar power systems in the province of Ontario will now earn some extra income to help pay for their systems, thanks to the Ontario Power Authority. Ontario is learning by example from the success of similar European programs. This new program is encouraging a flurry of solar industry construction activity aimed at taking advantage of the new electricity buy-back program. Paul Gipe, a wind power expert, from California calls the result revolutionary: “the most progressive renewable energy program in 20 years in North America.”

Leonard Allen, who runs a small solar panel company here, finally has something beneficial to tell callers, he says. For the first time, he can assure it won’t take 50 years to recoup the money they spend on a rooftop solar system.

Canada’s Ontario province has ordered local utility companies to pay homeowners or businesses for any electricity they generate from small solar, wind, water or other renewable energy projects, starting next month.

The plan is unique in North America, but it is modeled after similar schemes in Europe that have spawned a boom in small “clean energy” projects. Critics say paying for such electricity is not the most affordable source for utilities, but advocates say it is the cleanest and most environment-friendly.

In Ontario, the program has brought a rush of activity. Homeowners in Toronto are climbing onto roofs to add solar panels.

A cooperative of small investors are raising money to build five large wind turbines to harness Lake Huron winds. Others are eyeing the locks of a St. Lawrence Seaway canal for small hydro-turbines.

Farmers are looking at manure piles and calculating the profits of using organic decomposition to create methane gas that can make electricity.

There’s a tremendous interest, at all levels, from well-organized business consortiums to small homeowners,” said Tim Taylor, a spokesman for the Ontario Power Authority. “The impact in megawatts is going to come from the larger projects, but there’s a tremendous momentum found in small, backyard projects.”

We love the idea,” said Keith Stewart, an energy specialist at World Wildlife Fund Canada. “The small stuff adds up. This model should be taken right across North America.”

A grass-roots effort

The growing chorus of cheerleaders for the program say it is an example of the kind of individual, grass-roots effort that many see as the solution to intractable problems ranging from energy shortages to global warming.

The Ontario program was set in motion after politicians promised to shut down aging coal-fired power plants but faced the reality of growing electricity demands.

Advocates of renewable energy, some of them veterans of a successful campaign to erect a large windmill in downtown Toronto, intervened. They urged provincial authorities to use an economic spur to create hundreds of small electricity generators in hopes of avoiding building larger, expensive coal, gas or nuclear plants.

They brought Paul Gipe, a wind power expert, from California to lead the successful campaign. Gipe calls the result revolutionary: “the most progressive renewable energy program in 20 years in North America.”

Gipe noted that while some local utilities in the U.S. allow customers to send power back into the grid, there are no programs that pay a premium for generating the electricity.

Pay for producing

Starting in November, the 90 or so local utilities throughout Ontario will start paying anyone producing solar power for 42 cents a kilowatt hour. Wind, hydro or bio-electric production will bring 11 to 14.5 cents a kilowatt hour.

In addition to getting paid for making electricity, home-owners and businesses slash their own electricity draw from the grid, where power sells at an average of about 5.8 cents a kilowatt hour across the province. Advocates say it reduces the burden on the electric transmission lines, encourages conservation and may save the cost of a new plant.

Putting solar panels on the roof is a very tangible symbol of where your power is coming from,” said Ron McKay, an artist and graphic designer who helped form a co-op in his east Toronto neighborhood to buy solar panels at a bulk price. “You start to conserve. You don’t leave all the lights on. You change your light bulbs to efficient ones and start looking at your appliances.”

Ontario’s pricing scheme, called a standard offer contract, brought a flood of new interest to McKay’s solar-buying co-op, and has produced at least two similar co-ops in other Toronto neighborhoods.

Better than watching TV’

Members gleefully trade stories about watching their electric meters reverse on sunny days, putting electricity into the power grid rather than taking it out. “One woman said it’s better than watching TV,” McKay said.

Utility companies initially were wary of the administrative burden of purchasing power from thousands of customers. And there are technical problems. For example, utility linemen have to ensure that the small producers are disconnected from the grid when they work on electric lines.

Critics also say the cost to buy the power is higher than it would be from a conventional power plant, or an efficient big wind farm. Large contracts to build big projects is the North American norm.

Advocates counter that the prices set by the new Ontario program are too low. The 11 cents paid for wind power and small hydro may be rewarding, they say. But the $10,000 to $15,000 needed to buy a typical residential solar array means it could take 15 years to recoup the investment at the price offered to sell solar electricity back to the utility in Ontario.