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Contains FAQs about general solar topics that don't fall into a more specific category.
Solar energy applications are many and varied ranging from planning, policy, solar architecture and building construction to different kinds of equipment and their applications, and technical engineering. The information ranges from conceptual to technical. The Arizona Solar Center website provides for these different aspects of "solar and renewables" and for a variety of connections to a multitude of resources. Please review the site for the aspects of solar you are interested in, and use the resources available to you on the site.
There are no Arizona or utility rebate incentives on solar systems. There are Arizona and Federal tax credits and/or rebates that may apply to your situation. See Renewable Energy Incentives
This inquiry is best met by direct contact with the various non-profit organizations and for-profit businesses. The Arizona Solar Center's Resources Directory is a good place to start.
[Answer content currently under review - 12/10/2016]
Table 1: Net cost of a 5kW system
Is an individual who designs and installs his or her own solar energy device entitled to take the solar energy credit?
Yes. The solar energy device must meet the required criteria except for the warranty and professional licensing requirements. The value of your own labor is not allowable for tax credits, only out of pocket costs.
Some points to consider:
The Arizona Solar Center is not currently hiring. However, we suggest you consult the on the American Solar Energy Society website ( ). They have jobs posted in the solar energy area. Our own Internet site has many links to sources of information on renewable energy as well.
Internships are also possibly available from individual companies. We suggest you contact them directly. And there are many internship programs you should be able to find on the Internet. Among them is the Environment and Energy Study Institute ( ) in Washington, D.C. Their telephone number is 202-628-1400. Their job and internship board can be found at .
Solar cooking - I am making a solar cooker. What is the best absorbing material or paint that I can use to coat the surface in order to maximize solar heating?
In line with the simplicity and availability of the other materials we have used 1) black tempera paint (needs a very good adhering surface, cardboard or well sanded metal. 2) Barbecue black spray paint (This is formulated for use around food and is our preference) 2) Black latex paint (longer seasoning time.) Only the outside of pots and jars is painted; never the inside where there would be contact with food. Black is the traditional color, however, any dark color will work - red, green, blue, brown.....Whatever is available. The surface of metal or glass needs to be clean and scrubbed with sand to help the paint stick. Any of the paints need to be well dried in the sun to release the initial vapors, then baked in a solar cooker until all remaining vapors have been driven off.
Some people say that solar power is actually less efficient in the Valley of the Sun because sunshine here is offset by the heat here. Is that true?
You may follow current news releases on our front page of the website under 'Featured', our 'News Feed', the blog section, and the Twitter section.
What are the mirrors and solar panels that were formerly located near the intersection of University and McClintock in Tempe?
ASP currently has over 1000 MW of combined company-operated and distributed residential and commercial PV capacity.
SRP in 2016 reported 117.5 MW of residential PV, 52.7 MW of commercial, 91.9 MW of investor owned utility scale PV, and 381 MW of SRP owned PV systems.
TEP owns three PV plants and operates two others which are rated at a combined capacity of over 16 MW (outdated).
To understand you energy usage, get a summary from your utility.
A smart grid is a segment of the electrical distribution grid that uses information and communications technology to gather data, such as information about the plentiful availability or short-term shortage of electricity from grid suppliers and the electricity demand-oriented behavior of consumers, and act on it in an automated fashion. As more homes and businesses become equipped with solar electric systems, and eventually with energy storage devices, smart grids will become more and more important in terms of balancing electricity supply and demand on a real-time basis. The main goals of smart grids are to improve the efficiency, reliability, economics, and sustainability of the production and distribution of electricity.
Passive solar uses building and site elements and natural processes to accomplish a given task (comfort, water heating, air movement, etc.) with no, or minimal, mechanical and electrical equipment. Active solar technologies include PV and solar water heating systems and utilize mechanical and electrical equipment.
Please see the Arizona Solar Center Calendar (not presently implemented- will return soon)
Some information is available on the Overview of Arizona Courses page.
To many, PVs lead the way because costs are dropping rapidly, supplies are increasing, emissions are non existent, there are few if any moving parts, the maintenance effort is small, transmission lines can be minimal or even absent. Passive solar design is even better; that is, design our buildings so that we don’t need as much electricity in the first place.
In Germany solar development owes much of its success to their so-called feed-in law. Here’s a web site that concisely describes how it works: .
Here are the basics
In other words, the German government subsidizes solar power in order to help it get a firm footing. They do the same, as it says above, for other renewables, but at a reduced rate.
In Japan , the competing cost of conventional electricity is so much higher that it goes a long way to make solar an economically sensible choice.
Includes FAQs about PV systems.
Your site must have clear, unobstructed access to the sun. Buildings, trees or other vegetation should not shade your site. South-facing roof exposure is best, but roofs facing east and west may be OK. If a rooftop is not available, your PV system can also be mounted on the ground.
A small PV system can use as little as 50 square feet. A larger system, to meet the needs of a typical household, would use between 300 to 600 square feet. As a rule of thumb, 100 square feet of PV area produces 1 kilowatt of electricity.
Solar Panel Size - If you have a solar panel with 25 individual modules, is it really different compared to one large panel of the same size. Why is it different?
As you may know, solar panels come in many sizes. There are two basic types, photovoltaic and solar heating. Photovoltaic panels have solar cells that produce electricity. Solar heating panels can be made to heat either liquids such as water, or air. Most of my comments will refer to the photovoltaic or solar electric panels.The photovoltaic panels are more properly called modules by the solar electric industry. Most of the photovoltaic modules have a glass front called a superstrate) that provides protection from the elements (rain, etc.) while allowing sunshine to reach the solar cells. The solar cells are attached to the superstrate with a clear plastic that is in the form of a plastic sheet before the solar cells are laminated (stuck to) the glass by a combination of heat and pressure while a vacuum is applied to the assembly to minimize any bubbles in the plastic.
While this is in theory a simple process, it becomes more difficult the larger the photovoltaic module. This difficulty tends to limit the size of photovoltaic modules.
In general, the larger a photovoltaic module, the lower the cost per square foot, up until the maximum practical size is reached. There are some other considerations when considering the size of a photovoltaic module for any particular application (power plant, home, cabin, remote telecommunications site, etc.).
Please see these articles for detailed explanations of how Photovoltaic (PV) technology works:
The AZ Solar Center and AZ Solar Energy Industries Association provide lists of PV retailers. Retailers either can provide installation or can refer you to installation contractors in your area. Try to find a company located in the area where your system will be installed. Price is only one factor when selecting a PV company and/or contractor.
To estimate the best system size for your home or business, examine your electricity usage for the past 12 months.There are ‘Solar calculators’ on the web that will give ballpark cost and performance estimates.
If you want your PV system to meet half of your electricity needs, then you should size it to meet half of your annual electrical usage. Alternatively you can offset only a small portion of your electricity bill with a single PV panel.
You will need to enter into an Interconnection Agreement with your utility. This agreement addresses the terms and conditions under which your system will be safely connected to the grid. The agreement also specifies the metering arrangements (called net metering). Net metering allows you to "bank" any surplus electricity your system generates on the electric grid. Excess electricity might be generated during the day when your system produces more electricity than you need. Your meter would simply run backwards to record the amount of electricity banked on the grid, allowing you to use an equal amount of electricity later without incurring any additional cost. If you use more electricity from the grid than you have banked, your utility will charge you monthly for the difference. If you select a rate plan with Peak and Off-Peak periods, the utility will most likely account for the net metering by rate period.
FAQs about solar water heating and other solar thermal technologies.
A power tower is a type of concentrating solar power (CSP) technology that uses flat mirrors which track the sun and reflect light onto a collector at the top of a tower. The PS10 and PS20 facilities have been operated since 2006 and 2009, respectively, in Spain by Abengoa Power. The PS20 plant utilizes 1255 heliostats spread across 210 acres to produce steam in a collector at the top of a 541' tower. The steam turns turbines to generate 20 MW of power.
Contains FAQs about passive solar and other green building topics.
Approaches to passive solar are contained within concepts of thermal mass design; thermal skin design; composite design; with direct gain; indirect gain; and isolated gain approaches for heating and thermal sinks and diurnal dispersal techniques for cooling. Please refer to the website section titled Solar Architecture for a tutorial on the variety of approaches and strategies for passive heating and cooling.
There are a variety of passive system solar buildings throughout the State of Arizona., and some are identified in the website section titled Solar in Arizona. Additionally, contact statewide solar organizations like the Arizona Solar Energy Association (Regional Director in your region), and/or local solar architects (listed in the website section - Products and Services) for locations of buildings incorporating passive design in your area. See this article
These articles contain descriptions of how Arizonans have used a variety of techniques to reduce their energy usage.<< Link not working
Contains FAQs about regs, laws, regulatory agencies, etc.
The Arizona Legislature passed a bill in 2007 prohibiting homeowners’ associations (HOAs) from restricting the installation or use of solar energy devices. The legislation only authorizes an HOA to adopt reasonable regulations on the placement of the solar energy devices. (HB 2593) provides the full text of the bill in a PDF formatted file.
FAQs of interest to solar/renewable energy practitioners.
The Arizona Registrar of Contractors does not have any specific solar license, but considers this to fall under the CR11 general electrical license. There is a special solar only domestic hot water license. A minimal bond is required.
FAQs about the solar energy industry.
In the specific case of idling or lightly loaded electric motors, KVAR units (kilovolt-ampere-reactance units or power factor correction capacitors) actually do save energy. In this case, the KVAR units reduce the voltage and correct the power factor (a measurement of the phase difference from applied ac voltage and the resulting current), and save energy. The motors also run cooler and last longer. But in most cases, such as air conditioning, refrigerators, and the like, the motors are fully loaded and there are no savings.
In the case of commercial accounts, the utility uses meters that measure both the real power (watts) and the reactive power (volt-amperes reactive or VAR) and charge for the VARs if they constitute more than a certain percentage of the meter reading. This is important to utilities because while the VARs do not represent real energy, they do cause excessive currents that the utility needs to invest in larger equipment to handle. Measurement of VAR in residential service is very uncommon. These KVAR units do reduce the VARs and lower electric bills, but only for commercial service. In the case of master metering for connected buildings such as apartment complexes, the utility may be charging for Power Factor, in which case the KVAR units could be beneficial.
We are not aware of any damage coming from KVAR units.