Snow-coatged solar hot water heating panels on a Poughkeepsie NY rooftop (C) 2013 Daniel FriedmanSolar & Renewable Energy
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Solar energy design & products home page:

Solar Energy System Types, Uses, Installation Best Practices.

These solar energy articles discuss how to choose, install, diagnose, & repair renewable energy systems for buildings including active and passive solar heating & solar hot water heating systems, solar powered electrical systems (photovoltaics), along with building insulation & ventilation design & retrofit tips to save energy where solar or other alternative energy systems are in use or planned.

We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.

Solar Energy Designs & Retrofit Improvements in Buildings

Solar electrical power array, San Miguel de Allende (C) Daniel Friedman

The green power solar electrical panel array shown above is distributed by Desmex Solar and is installed in San Miguel de Allende, Mexico.

The solar energy system shown here and just below provides all of the electrical energy required by a small restaurant, including powering lighting and nine refrigerators and coolers in the building.

To find what you need quickly, if you don't want to scroll through this index you are welcome to use the page top or bottom SEARCH BOX to search InspectApedia for specific articles and information.

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Our page top photo illustrates an extensive photovoltaic solar panel system installed on a building providing commercial rental space in New Paltz, N.Y. The property owners expect a rapid payback on the system cost thanks in part to government incentive program assistance.

Satisfied with the performance of the solar panels in reducing building electrical costs the owners intend to install a similar system on residential apartment space in New Paltz as well.

Solar electrical power array, San Miguel de Allende (C) Daniel Friedman

Solar Energy Articles, Information, Products, Sources

Solar heating installation (C) Daniel FriedmanOur articles listed below provide detail about solar energy sources, installation, maintenance, inspection, diagnosis, and repair.

Articles in this series include solar energy, solar heating, solar hot water, and related building energy efficiency improvement articles including material reprinted/adapted/excerpted with permission from Solar Age Magazine - editor Steven Bliss.

We include links to solar design guides and other authoritative sources.

Our photograph (left) shows solar panels, both photovoltaic and domestic hot water heating systems, on a rooftop in Surprise, Arizona.

According to the Pennsylvania DEP who provide a nice introduction to solar power, solar energy systems are divided into three major categories: passive solar systems, solar-thermal systems, and photovoltaic solar systems.

The text below is adapted and expanded upon from that source:

Definition of Passive Solar Systems: Using Building Design Features to Take Advantage of & Control Solar Heat Gain

Direct solar gain (C) Daniel Friedman

Passive solar design (PASSIVE SOLAR DESIGN METHOD) takes advantage of a building's structure to capture the sun's heat, either storing or distributing it, reducing the need for conventional heating, cooling and/or lighting.

Examples of passive solar design include large, south-facing windows, dark colored tile floors (BLOCKBED RADIANT FLOORS - SOLAR DESIGN), stone fireplaces, brick interior walls, "sunspaces" (or greenhouses) and super-insulation.

Passive solar buildings are often equipped with features, such as overhangs (SOLAR SHADES & SUNSCREENS) and ventilation systems, which keep them cool in the summer months and warm in the winter months.

Passive solar buildings may also make use of special window glazing (SUNGAIN, FILMS, LOW-E GLASS) to control un-wanted heat loss in cold weather and un-wanted gain in hot weather.

See PASSIVE SOLAR HOME, LOW COST for an example of a low-budget passive solar design.

The effectiveness of passive solar heating is discussed at PASSIVE SOLAR HEAT PERFORMANCE.

Our passive solar gain photo (above left) is from the author's New York home.

Definition of Solar-Thermal Systems: Using Solar Energy to Heat Water to Operate Electricity-Generating Turbines

Power plants often use fossil fuels as a heat source to boil water. The steam from the boiling water then rotates a large turbine, activating a generator that produces electricity. Solar-thermal concentrating systems use sunlight as the heat source, eliminating the need for fossil fuels.

There are three types of solar-thermal concentrating systems & parabolic troughs, parabolic dishes and central receivers. Parabolic troughs, primarily used for industrial purposes, are curved reflectors that focus sunlight into a line receiver in which fluid is heated.

Parabolic dishes, also used in industrial applications, are bowl-shaped reflectors that focus sunlight into a small receiver through which passes a heat-transfer fluid. Central receivers, which have traditionally dominated the U.S. Department of Energy's solar thermal program, are sun-tracking mirrors that focus sunlight onto a large receiver.

Residential heating of water using solar systems is not in turn for the generation of electrical power as the PA DEP outlined above, but rather to produce domestic hot water (SOLAR HOT WATER HEATERS) or in some cases, heat storage or to heat swimming pools (SWIMMING POOL SOLAR HEAT, INDOOR).

Special applications of solar heating or boiling of water of interest to smaller-scale users includes SOLAR WATER DISINFECTION such as might be used at a remote cabin or in areas where potable water is not available.

Definition of Photovoltaic Cell Solar Systems: Using Solar Energy to Create Electricity in Arrays of Devices that Change Sunlight into Electrical Energy

Solar powered street lighting, Haddonfield NJ (C) 2013 Daniel Friedman

Photovoltaic (PV) cells, or solar cells, convert sunlight directly into electricity. [A photovoltaic cell is an electrical device made of layers of semiconductor materials that are excited by sunlight and give off electrical energy.]

As the sun strikes a PV cell (PHOTOVOLTAIC POWER SYSTEMS), the semi-conducting materials within the cell absorb the sunlight, producing electricity. Solar cells are often used as simple systems that power small calculators and wristwatches. More complicated systems provide electricity for pumping water, powering communications equipment, lighting homes, and running appliances.

In residential applications, photovoltaics are also popular for remote cabins where conventional electrical power is not available (REMOTE ELECTRIC POWER, PHOTOVOLTAIC).

A series of solar cells form a PV array or "solar panel." Between 10 and 50 solar panels are needed to power an average household. PV panels are installed on buildings in places of maximum sun and minimal shade in order to take full advantage of the sun's power. There is very little maintenance required to sustain solar equipment.

So long as panels are kept clean, they can last approximately 20 to 30 years. Also see SOLAR COLLECTOR EFFICIENCY COMPARISONS.

Our photovoltaic solar panel photo (above left) shows the use of passive solar energy to power street lighting in Haddonfield, New Jersey.

Solar Grid-Tied vs Distributed Solar Systems

Snow-coatged solar hot water heating panels on a Poughkeepsie NY rooftop (C) 2013 Daniel Friedman

Our photo illustrates snow-coated solar hot water heating system panels on a Poughkeepsie NY rooftop during snowy winter weather.

A solar grid-tied system links a series of solar panels through a power inverter to the utility's electric grid. The solar panels generate a direct current (DC) by drawing on energy from the sun.

The inverter then converts that direct current to an alternating current (AC), which electronic devices and appliances can use. Batteries are not necessary to supplement the system and any excess electricity generated by the solar panels is redirected by the inverter back into the grid where it can be used on other premises.

Distributed solar systems work independently from a utility's electric grid, using batteries to store the power. Similar to a grid-tied system, distributed solar panels typically use a power inverter to convert the direct current from the sun into an alternating current, to be used on location. However, some systems function without an inverter and run only DC appliances.

Index to Solar Energy Information at InspectApedia

Solar Water Heating Systems

Closeup of a solar water heater collector unit (C) Daniel FriedmanSolar water heaters use renewable energy - sunlight - collected in outdoor rooftop or ground-mounted solar collectors to heat water which is circulated by a pump between a hot water storage tank and the panels.

The upper end of a simple solar water heater collector is shown in our photo at left. Look closely and behind the corrugated plastic surface, at the top you can see the horizontal black tubing that moves water through the top end of this collector.

Solar water heaters have been in use for decades, with popular use at remote cottages or off-the-grid buildings and are likely to see increasing use in much of the world as energy costs continue to climb.

List of Solar Heating Systems, Panels, Controls, Components, Packaged Systems

Schematic of a solar water heater hookup (C) - Lennox IndustriesSketch at left courtesy of Lennox Industries.

Solar Heating Design, Installation, Repair Books, Solar Pumps, Manuals

Alternative Energy, Green Energy, Energy-Savings Topics & Articles Supporting Solar Energy Systems & Designs

See the ARTICLE INDEX link given below at More Reading.

Continue reading at PASSIVE SOLAR DESIGN METHOD or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.


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