The Solar PV Eclipse of 2017

Nat Geo Solar Eclipse Photo

How will the U.S. solar eclipse of August 21, 2017 be different from the eclipse that will occur in April of 2024? (Hint, this is not an astrophysics, geography or geometry question, but just to briefly answer these science categories, the path of the August 21, 2017 eclipse will be a slight northerly arc from Oregon to South Carolina and cover a swath about 80 miles wide; the 2024 eclipse path will be from Texas to Maine with a slight westerly arc, and cover a swath of about 70 miles wide.)

The difference between the two eclipses I’m referring to has to do with their effect on solar power PV (photovoltaic) systems. The effect of this year’s eclipse will be negligible mainly because the level of solar penetration – the amount of solar power being put into the electrical grid – is not that great.

However, the level of solar power connected to the grid will be significantly greater in 2024. If we had the same level of solar PV penetration now as we will have in 2024, the eclipse could create instability in the grid because of voltage collapse along its path. Interestingly, we will have a different type of solar generation system when the 2024 eclipse occurs. Energy storage with smart power monitors and utility controllable inverters will be the standard in 2024.

Fortunately, there will be no noticeable difference in the effects to grid stability. Without energy storage and smart inverters that continually communicate with the utility, the effects of the eclipse would definitely be felt when the next eclipse occurs in the U.S., but we will sail through it as we would hope to, with our solar-safe glasses, a lawn chair and no worries about its effects on solar electric systems.

Enjoy the experience

Kelly Provence
Solairgen School of Solar Training Technology
IREC Certified Master PV Trainer
NABCEP Certified Professional PV Installer

Graphis of Excess Energy to the Grid

Alternative to PV System Net Energy Metering: Improving Grid Stability

What alternative to net energy metering (NEM) with PV systems will improve the grid stability and reduce consumer dependence on it? Self-consumption energy storage PV systems are the answer.

Solar PV installations continue to grow in the residential and commercial sectors. Integrated energy storage continues to grow along with the PV installations, and both of these are growing at a strong pace in the industry.

NEM can be calculated on a daily, monthly or annual basis; most NEM agreements are calculated monthly. Whether the consumer generated energy is used by the consumer or sent back into the grid, the energy consumption is reduced at the retail rate. The problem with this setup is that most of the energy goes back into the grid during the middle of the day (solar hours) when consumer energy demand is low; this does not improve grid stability, and can make it worse. The graph below shows the typical energy consumption vs. solar energy generation for a residential customer.

Graphic of Energy Out to Utility

PV systems with energy storage can change this with the batteries storing energy that would otherwise be sent into the grid.

Graphis of Excess Energy to the Grid

The stored and redistributed solar energy will improve grid stability in residential by reducing demand during peak usage times. If time of use metering (TOU) is in place, this setup will reduce energy consumption during afternoon and evening high rate periods. This increases financial savings to the PV system owner.

The following graph shows the typical U.S. grid load demand curves for all electrical energy users.

Total Demand

Residential electrical energy customers with interactive PV systems are supplying power during the time of day when residential load demand is not at its peak. PV systems with energy storage can operate as self-consumption systems and improve their return on investment. Grid stability is improved to the point where grid operators can see reduced operating cost as this type of PV system penetrates more of the NEM market.

This type of PV system can also provide the customer with critical load circuits that will operate during a grid outage. Everyone wins with these systems and NEM policies are no longer a factor with the customer’s financial rate of return.

Kelly Provence

Residential Solar: Which is Best – Ownership or Community Solar?

Solar Farm in Florida

Residential Solar: Ownership or Community Solar

Which is best for you? It really depends on you, your house and your utility. Consider the factors involved in placing a system on your home:

1. Is there room on the roof or ground for the PV array? The average 2000ft² home uses about 60kWh to 80kWh per day. To offset half of that energy a PV array would need to be 8kW to 10kW, and it would occupy an area of 600ft² to 800ft² on the ground, or it would require a roof area of 800ft² to 1000ft² due to required margins and offsets.

2. Will the PV array be a visual detriment to the home? It is possible to have the array visible and attractive with proper selection of materials, but a Homeowners’ Association could be a problem if the array is visible from the street.

3. Will it be financially beneficial? The matter of cost and return on investment (ROI). The federal tax credit provides a 30% reduction on total system cost. If you cannot take this credit, the value is diminished. If you live in a location where other incentives are in place, be sure that you qualify for those incentives.

4. The last factor is your personal reasons for owning a system. Seeing the array on your property, and knowing you’re saving energy and money on your energy bill is an important factor. Backup power is also an important motivator for owning a system, but if power is rarely lost in your area, a fuel generator may be a better option.

Consider these factors that would make community solar a good option:

The alternative to owning a system outright may be Community Solar programs. These programs are not available in all locations but their availability is growing quickly. Community solar farms are usually owned by the utility company. The customer can buy power from this farm through a program offered by the utility.

1. If locating an array on your home or property is a problem due to space or curb appeal restrictions, this may be a good alternative. These systems are huge and usually located within a few miles from your home. If it is a true community solar farm, there will be an area where you and your family can visit to learn about its function and performance.

2. The performance of the PV system will be maximized regarding the solar resource and the financial return on investment by the utility. This will provide the lowest cost for solar electric generation passed on to the utility customer.

The future of residential solar will be a mix of individually owned PV systems with energy storage, and community solar farms. Both will enhance the viability of the grid and reduce costs of electricity during the lifespan of the PV system. You should be able to pick the one that best fits your lifestyle and goals.

Kelly Provence CEO

Solairgen

Solar Power World and “State of Solar” for U.S. 2015

Crash course in U.S. solar

We like to share good information about solar from other sources and this is a great article with good information about the solar market in the U.S. today. Residential and commercial solar installations have increased as costs have gone down, and the number of solar panel installations has increased dramatically as a result. It’s a good time to get into the market.

SOLAR TRAININGCLASS LIST
ManInstalling6A

Choosing a Solar Installer 101

The U.S. is growing in residential and commercial solar PV installations – and fast. If you’re a home or business owner, owning and paying for a solar PV system is easier than ever, but there are guidelines for potential solar PV owners to make the process successful – starting with who you choose to install your PV system. When you enter solar installer search criteria into your search engine you’ll get a long list to choose from. So how can a home or business owner tell who is, or isn’t, a competent professional installation company?

First, at least one person with the contracting company must be a licensed general contractor or licensed electrical contractor to legally write a contract for the PV installation. Also, it’s a good bet that if an installation company has been in business for a few years, they’ll have at least one NABCEP Certified Installation Professional on their team. A NABCEP Certified Installation Professional has been through many hours of advanced solar training, has experience installing and designing PV systems, and has passed a demanding nationally recognized exam. Ask questions. Reputable solar installation companies won’t mind answering them.

The solar training an installer gets can mean the difference between a qualified, competent installation professional and an installer who is less qualified, or just out for the money. Ask the company representative where they received their solar installation or solar sales training.

A solar training program that is IREC Accredited, or a trainer who is IREC Certified as a Master Trainer has achieved the highest level of quality and excellence in the solar industry today.  If the team you’re interested in isn’t NABCEP certified, it’s a good idea to make sure they were trained in an IREC Accredited program, or by an IREC Certified Master Trainer.

Of course, there is also word-of-mouth. Join Facebook solar groups where you can ask other PV system owners about their experiences. Solar is a long-term investment in your home, your business, your future and your family.  Doing your homework before contracting with a solar PV installation company could mean the difference between an installation that is reliable or one that requires expensive troubleshooting.

Leigh Hamilton
Solairgen School of Solar Technology

Atlanta-Buildings2a

SolarWindow Enters into Third Phase…

SolarWindow Enters into Third Phase of Technology Development Agreement with U.S. Department of Energy’s National Renewable Energy Lab (NREL)

02 Mar 2016
SolarWindow Technologies, Inc., the leading developer of first-of-its-kind transparent electricity-generating coatings for glass and flexible plastics, announced that it has entered into Phase III of its Cooperative Research and Development Agreement (CRADA) with the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL). The primary development goal of the Agreement is the commercialization of SolarWindow products.
NREL is recognized as one of the most respected and advanced solar-photovoltaic research institutions in the world. NREL scientists have been working side-by-side with SolarWindow Principal Scientist, Dr. Scott R. Hammond during the development of SolarWindow transparent electricity-generating coatings. SolarWindow is initially targeting the five million tall towers and commercial buildings in the United States, which consume almost 40% of the electrical energy generated.
“The prospect of skyscrapers generating electricity from see-through window products is very exciting,” said Dr. Maikel van Hest, a Senior Scientist in the Thin Film and Processing Group within the National Center for Photovoltaics at NREL. “Through our CRADA, we have been able to develop and test this technology using some of the world’s most advanced state of the art equipment. As a result, SolarWindow and NREL have advanced the technology by enhancing scale, efficiency and reliability.”
Under the terms of the Agreement, SolarWindow and NREL will continue to work jointly to enhance product performance, increase scale, and improve reliability; and develop new features and obtain important performance certifications required for a commercial rollout.
In addition, the team will focus on various SolarWindow product-specific goals, including:
  • Large scale window fabrication
  • Interconnection development for easy ‘plug-n-play’ on-site installation
  • Advanced performance measurement and modeling of SolarWindow when installed in various building types and geographies
  • SolarWindow performance under varying artificial and natural light conditions
  • SolarWindow can provide a one-year financial payback while producing 50-times greater energy than rooftop solar when modeled for a 50-story building, according to the company’s independent validation. For the same building, SolarWindow shows 15-times the environmental benefit of rooftop solar by avoiding 2.2 million miles of equivalent carbon dioxide emissions produced by vehicles, according to the company’s independently validated Power & Financial Model.
“With this CRADA extension in place, we’re one step closer to launching what is possibly the single greatest breakthrough technology in clean energy to help us overcome our dependence on fossil fuels,” said John A. Conklin, President and CEO of SolarWindow. “Keeping in mind that commercial buildings consume almost 40 percent of America’s electricity, our goal is to put a solid dent in reducing carbon emissions and offsetting a building carbon footprint while providing customers with clean electricity-generating solutions that make economic sense.”
SolarWindow Technologies, Inc.
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Converting Solar to Usable Energy

Photonic energy is a wave particle that travels at a speed of approximately 300,000 kilometers per second (186,000 miles per second). Almost everything reacts to this energy when contacted by it. The most common reaction is conversion to heat. Plants convert sunlight to chemical energy (complex sugar). The sugar is stored and used by the plant to live and grow.

Humans have also learned how to convert the solar energy to usable energy. We convert solar energy directly into two types of energy for use.

  1. Solar thermal (heat energy) is used for hot water and steam for power generation.
  2. Photovoltaic (solar electric) energy is converted from the visible light spectrum to power electrical appliances.

Solar Thermal Energy:

Solar Thermal energy can be used instantly and it can also be stored as hot water or oil in an insulated container. The storage is usually for no more than a day. This is the most efficient conversion of solar energy to usable energy although it may not be the most cost efficient method. Small-scale solar thermal systems require expensive equipment to capture solar energy, convert it to thermal energy and then store it for later use. The net conversion efficiency is around 30% for the average home.

  • The cost can be amortized over the lifetime of the system (15 – 20 years). Compared to heating water with electricity, the system reduced energy costs during the system lifetime. Compared to heating water with NG, the system may not reduce energy costs during the system lifetime.

Photovoltaic Energy:

Photovoltaic energy (PV) is used instantly since electricity travels close to the speed of light, although it can be converted and stored as chemical energy. Chemical energy storage such as electrolyte batteries or hydrogen provide 24-hour usage of solar electric energy. It also adds cost to the solar electric energy system. The net conversion efficiency of the average PV system without energy storage is around 13% to 16%. Energy storage will reduce that efficiency to 10% to 14%. Off-grid system net conversion efficiency is under 10%.

  • PV systems amortized over 5 to 10 years usually provide a positive return on investment. Over the life of the PV system (25 years), the return is 2x to 5x of the system cost. With energy storage added to the system cost, the lifetime return is 1.5x to 3x of the system cost.

Capacity Limiters for Photovoltaic Energy:

Peak solar hours occur during the six mid-day hours; this is when 80% to 90% of the photon energy is converted to electrical energy. This can be a problem for utilities if electrical energy is consumed during other hours of the day. Utility companies must balance the electrical power grid and provide stable voltage to their customers. A limited amount of solar electric energy can be fed into the electrical grid without causing voltage rise and collapse (around 10% of the electrical load). Increasing the capacity far beyond the 10% limit requires converting the electrical energy to another form of storable energy. Energy storage is necessary to extend the usage of solar electric energy.

  • Chemical energy storage (the electrolyte battery) is the most common method where electrical energy can easily be converter to and from chemical energy. The conversion efficiency is around 90% efficient. The cost of chemical energy storage is high, although several types of batteries are now on the market and prices are dropping. Charging the batteries requires hours for most technologies, although some technologies are faster than others. Residential systems are typically used for backup power when the utility power is lost. Commercial systems will use energy storage mostly for load stability and rate cost.
  • Hydrogen energy storage (fuel cells) is a growing technology where electrical energy is used to separate hydrogen from a molecule such as water. The conversion efficiency ranges between 60% to 90% depending on the method. The net efficiency is reduced much further if the hydrogen gas is concentrated for storage. Compressed hydrogen is very portable and lightweight. Non-compressed hydrogen would require massive storage space and would be impractical as a stand-alone system.
  • A couple of other methods of energy storage are flywheels and capacitor banks but neither have proven to be as feasible as chemical batteries or fuel cells.

Solar Electric Systems:

Solar electric systems produce around 1% of the U.S electrical energy generation; some areas of the U.S are experiencing close to 10%. Here is what is being done to satisfy electric grid stability as solar electric grows in capacity:

  • Correcting power factor problems: Most areas of the electrical power grid experience a lagging current because of inductive electrical loads. Solar electric inverters can correct some of that with their capacitors (capacitive loads).
  • Peak demand: When too many heavy electrical loads occur at one time, the electrical load demand is high, and very difficult and sometimes expensive to generate and manage. Distributed solar electric generation sites provide onsite power and reduce the peak load demand. Since rain and heavy cloud coverage reduce this capacity, energy storage can be installed to work with the solar electric system to produce power on-demand.
  • Load and cost management: Solar electric systems can be directed to produce energy during specific daylight hours when load demand is highest and/or when electrical rates are highest. Combining this with energy storage will increase the return on investment for the system owner.
  • Micro-grids and emergency power: Some solar electric systems with energy storage will be designed with extra storage capacity. These systems can operate and produce electrical power for several days or longer.

The applications identified above will allow solar electric system capacity to grow without limits.

Kelly Provence
Solairgen
www.solairgen.com

Solar Training Students

About Solairgen

IREC Logo Training ProviderSolairgen was the first privately held solar training class company in the eastern U.S. Our IREC Accredited solar training programs continue to provide students with the highest quality learning experience through state-of-the-art distance learning, classroom and workshops, and equipment used in our training programs. We offer complete, nationally accredited, online training and PV installation workshop programs for solar PV design and installation, as well as IREC Accredited online training for PV Sales and Design (Technical Sales).

Our online classes can be taken anywhere there is internet, but students come from all 50 United States to participate in our hands-on workshop, PV203 System Design and Installation. Many students come from outside the U.S. such as the Caribbean, Puerto Rico, Sub-Saharan Africa as well as Eastern countries including India, Bangladesh, Saudi Arabia and Egypt.

Solairgen prepares you for a career in solar installation, and can lead you to national certification as a PV Installation Professional and/or a PV Technical Sales/Business Professional. Students may begin their training with our online PV201 then advance their training and knowledge with PV203 System Design and Installation, PV-221 Advanced online training, then prepare for industry certification in our NABCEP PV Installer and PV Technical Sales Exam Preparation classes. Please see our Home page for more information about our comprehensive career training classes program – or call if you have any questions. We’ll be happy to talk to you about your career plans: 706-867-0678 or 800-262-7560.