Forty years ago, Harold Hay, 98, invented a simple, inexpensive way to heat and cool a home using the sun’s rays, but without the panels and wiring that come with conventional solar energy systems.

He’s been pushing for its adoption ever since, trying to find footing in each of the solar industry’s last three boom-and-bust cycles.

Yet, despite the merits of his pioneering technology, the energy establishment has shown only fleeting interest.

As Gore said, quoting Upton Sinclair “it is hard to get someone to understand something — if their salary depends upon not understanding it.”

When it comes to climate change, those who refuse to act are mostly those without imagination, or those whose financial interests support the status quo. Passive solar systems cost little or nothing to operate, and so represent a serious threat to the fossil fuel industry.

Hay’s system keeps a house between 65-75 degrees year-round with virtually no electricity. What’s the catch? It requires the house to be built from scratch, and built strong enough to hold a roof-sized pond of water. Still, to have no heating or cooling bills for the life of the home? Wow. [Click the story link at the top of the article for a video of this house and how the system works.]

Even if people didn’t want to have flat roofs, I see no reason why they couldn’t heavily insulate their home and locate the solar pond elsewhere on their property. Then they could use pumps and heat-exchangers to take advantage of the water’s thermal mass. Certainly this could be a great way to cool apartments and commercial buildings as well.

Cheap electricity, fuel oil, and natural gas have kept people using energy-hogging central furnaces and forced-air systems, generating countless gigatons of CO2 for decades. Solutions such as the Skytherm house are as simple and elegant as it gets and produce no CO2. Only two things stand between our current situation and a clean planet and better life: greed and inertia.

Carbon taxes will make the status quo prohibitive, and force many of these types of solutions. There are many details to be worked out, of course, but a better national energy policy can turn this sad situation of needless energy waste around. There’s no excuse anymore, it’s just common sense. It’s high time for solar energy to stop being a science project and get mainstreamed

Just as solar energy can heat the water for a building, it can also heat and cool the air.

Space Heating

A solar space-heating system can consist of a passive system, an active system, or a combination of both. Passive systems are typically less costly and less complex than active systems. However, when retrofitting a building, active systems might be the only option for obtaining solar energy.

Passive Solar Space Heating

Passive solar space heating takes advantage of warmth from the sun through design features, such as large south-facing windows, and materials in the floors or walls that absorb warmth during the day and release that warmth at night when it is needed most. A sunspace or greenhouse is a good example of a passive system for solar space heating.

Passive solar design systems usually have one of three designs:

• Direct gain (the simplest system) stores and slowly releases heat energy collected from the sun shining directly into the building and warming materials such as tile or concrete. Care must be taken to avoid overheating the space.
• Indirect gain (similar to direct gain) uses materials that hold, store, and release heat; the material is located between the sun and living space (typically the wall).
• Isolated gain collects solar energy remote from the location of the primary living area. For example, a sunroom attached to a house collects warmer air that flows naturally to the rest of the house.

For more information about passive solar space heating, visit the EERE Passive Solar Heating, Cooling, and Daylighting page.

Active Solar Space Heating

Active solar space-heating systems consist of collectors that collect and absorb solar radiation combined with electric fans or pumps to transfer and distribute that solar heat. Active systems also generally have an energy-storage system to provide heat when the sun is not shining. The two basic types of active solar space-heating systems use either liquid or air as the heat-transfer medium in their solar energy collectors.

Liquid-based systems heat water or an antifreeze solution in a hydronic collector. Air-based systems heat air in an air collector. Air-based solar heating systems usually employ an air-to-water heat exchanger to supply heat to the domestic hot water system, making the system useful in the summertime. Both of these systems collect and absorb solar radiation, then transfer the solar heat directly to the interior space or to a storage system, from which the heat is distributed. An auxiliary or backup system provides heat when storage is discharged. Liquid systems are more often used when storage is included.

Here is a summary of the many different types of active solar space-heating systems:

Medium-temperature solar collectors are generally used for solar space heating. Solar space heating systems operate in much the same way as indirect solar water-heating systems, but they have a larger collector area, larger storage units, and more complex control systems. They are also usually configured to provide solar water heating and typically provide 30% to 70% of the residential heating, or combined heating and hot water, requirements. Active solar space-heating systems require more sophisticated design, installation, and maintenance techniques.

• A very economical, but specialized space heating system is based upon use of transpired air collectors, mounted as an exterior cladding on a south-facing wall. These systems are used for ventilation preheating. This system heats only outdoor air. These collectors are unglazed, and a blower or fan is used to draw air through perforations in the wall to deliver ventilation air into the building. Solar ventilation air preheating systems are generally used in commercial and industrial applications that require large quantities of ventilation air, including: a) buildings that require much outdoor ventilation, such as warehouses, large manufacturing plants, and airplane maintenance hangars; b) crop drying; and c) pre-heatingof boiler combustion air.

Space Cooling

Cooling and refrigeration can be accomplished using thermally activated cooling systems (TACS) driven by solar energy. These systems can provide year-round utilization of collected solar heat, thereby significantly increasing the cost effectiveness and energy contribution of solar installations. These systems are sized to provide 30% to 60% of building cooling requirements using solar, with the remainder usually dependent on TACS fueled by natural gas. The TACS available for solar-driven cooling include absorption systems and desiccant systems. Generally, solar cooling is not used because of the high initial costs of TACS and the solar fields needed to drive them.

• Solar absorption systems use the thermal energy from a solar collector to separate a binary mixture of an absorbent and a refrigerant fluid. The refrigerant is condensed, throttled, and evaporated to yield a cooling effect, which is then re-absorbed to continue the cycle. Double-effect absorption systems (which use the heat twice in series) are about twice as efficient as single-effect systems, but require significantly higher input temperatures. Because of the high temperature requirements of absorption cooling systems, evacuated-tube or concentrating collectors are typically used.
• Solar desiccant systems use thermal energy from the solar collector to regenerate dessicants that dry ambient air; they then use that dry air in indirect and/or direct evaporative stages to provide cooled air to the load. The solar heat is used to regenerate the desiccant, driving off the absorbed water. Some systems use flat-plate collectors at intermediate temperatures.

The Law of Conservation of Energy:

• Energy can only change from one form to another.
• Energy can not be created or destroyed.

Solar Energy is the energy from the Sun.  The Sun is a big ball of heat and light resulting from nuclear fusion at its core.  The nuclear reaction releases energy that travels outward to the surface of the Sun.  Along the way to the surface the energy transforms so that by the time it is released it is primarily light energy.  Sunlight.  The two major types of solar energy that make it to Earth are heat and light.

Solar energy is often called “alternative energy” to fossil fuel energy sources such as oil and coal.

One example of our use of solar heat energy is for water heating systems.  A solar panel is used to collect heat.  The heat is transferred to pipes inside the solar panel and water is heated as it passes through the pipes.  The hot water, heated by the Sun, can then be used for showers, cleaning, or heating your home.

We also use solar thermal energy through passive solar designs.  Windows or skylights in your home can be designed to face the Sun so that they let heat into the house, keeping you warmer in the winter.

The light energy from the Sun can be transformed into electrical energy and used immediately or stored in batteries. Photovoltaic (PV) panels are the devices that convert light energy into electrical energy.

Energy changes from one Form to Another.

Let’s look at a solar powered vehicle that runs on electricity directly from solar energy as a simple example in the transformation of energy from one form to another.

• Sunlight hits the PV panel and the panel transforms the light energy into electrical energy.
• The electrical energy (electricity) passes through the wire circuit to the motor.
• The motor transforms the electrical energy into mechanical energy to turn the drive shaft which turns the wheels.
• The wheels rotate on the ground to move the vehicle transforming mechanical energy into vehicle motion (kinetic energy).

Solar Vehicle Ideal Energy Chain:

Light Energy >> Electrical Energy >> Mechanical Energy >> Kinetic Energy

Energy transformation is not perfect…..

The above case is ideal because not all systems are perfect and in reality there will be losses of energy from our system.

In a simplified view of this case some losses will be from:

• friction of electrons passing through the wires;  this is released as heat energy.
• friction of the drive shaft or wheels on the ground;  this is released as either heat or sound energy.

Even with these losses the law of conservation of energy still holds.  The amount of energy into a system will always equal the amount of energy out of a system.

There are so many reasons why you should take advantage of DIY home solar energy that it’s actually kind of hard to know where to begin. The greatest benefit that leaps out to so many is the opportunity to create an endless amount of free electricity to power your home.

The other benefit will be appreciated by those that are concerned about the carbon footprint that we are leaving on this galactic rock that we inhabit called Earth. Fossil fuels emit pollutants into our atmosphere every time they are used and are a finite source of energy that are not only very expensive but are also being depleted by the day.

The increased demand by developing nations such as China and India are driving the costs of fossil fuels used in the home including heating oil and natural gas higher and higher. Couple that along with the ever present political turmoil in the Mideast and you have a recipe for runaway fuel costs.
Unless you are wealthy and money is no object then a DIY home solar energy system is hands down the way to go. You can go online and purchase an instantly downloadable e-book that contains complete plans for building and installing your own solar panels as well as videos that will walk you through how to do it step-by-step.

Constructing your own home solar energy system is relatively inexpensive, especially when compared to commercially built and installed solar panels. You can build your own photovoltaic solar cells and string them together into a solar panel that is every bit as good as a commercially constructed one for a fraction of the cost.

Commercial solar energy systems for a home of average size can run upwards of $20,000 and above. You can build your own solar panel and install it yourself for about $200 or even under $100. And once more, there are no special skills required to build your own solar panels and all the parts that you will need can be purchased at your neighborhood hardware store.

You can begin your foray into DIY home solar energy slowly by building a single panel which will generate enough electricity to run many of your household appliances. When you begin to become proficient at building the panels you can build more and add them to what you have already created which will of course enhance your ability to generate electricity free of charge.

And just think about this… it is very, very possible to generate enough electricity to completely power your home and no longer have to pay those expensive utility bills. Not only that but you can also go completely off the grid and even produce enough electricity that you can sell it back to the power company for a profit. It’s a beautiful thing isn’t it? And it’s all within your reach.