With utility-scale solar projects multiplying across the US, the quality assurance of solar panels has become a major subject of owners’ and investors’ focus. The success of multi-million dollar systems hangs in the balance and stakeholders have vested interests in the reliability of the products being installed.
Co-leading an international program, the Department of Energy’s National Renewable Energy Laboratory (NREL) has turned its attention to assessing and assuring the quality of solar panels.
Offering an alternative to solar leasing programs, the Photovoltaic Division of Mitsubishi Electric US, Inc. has introduced a new consumer finance program. The new finance program for solar pv system ownership is being offered to qualified homeowners through Mitsubishi’s authorized solar contractors.
Gina Heng, vice president and general manager of Mitsubishi Electric US, Inc.’s Photovoltaic Division, said in a recent statement, “Consumers who wish to install Mitsubishi Electric state-of-the-art photovoltaic modules now have the ability to finance their purchase.”
Mitsubishi’s Solar Energy Technology
Mitsubishi Electric is one of the most established solar providers in the industry, with 50 locations throughout North America, and approximately 3,600 employees. In addition to solar photovoltaic modules, Mitsubishi Electric US group companies’ principal businesses include a wide variety of electronic and electrical products. Some of these products include semiconductor devices, automotive electrical components, factory automation products, electric utility products, heating and cooling products, elevators and escalators, and large-scale video displays for stadiums and arenas.
Designing, engineering, and manufacturing high quality solar panels, Mitsubishi has over 40 years of experience developing solar energy technology, and over 90 years of electronics manufacturing expertise. Mitsubishi also offers a 25-year limited warranty to all residential, commercial, and government customers, ensuring an optimum return on investment.
An Innovative Finance Program with Flexibility
Mitsubishi Electric US launched the innovative consumer solar finance program for its contractors to help boost their sales. Heng pointed out the advantage of the new program, saying, “our contractors can now offer more financial flexibility to their residential clientele.”
The new Mitsubishi program offers consumer finance for solar pv systems through a leading provider of residential solar finance. According to the Mitsubishi statement, additional advantages for the homeowners include lower monthly payments than leasing, and financing features not available through many other lenders. Consumers will also know in real-time if their loan is approved, through advanced consumer credit underwriting. Qualified borrowers may apply to finance their solar pv system for amounts up to $60,000.
Contractor Training Provided by Mitsubishi
“In order for contractors to fully leverage this new program,” said Mitsubishi PV Division Vice President Heng, “we want to ensure that they understand how it works and how it can benefit both them and their customers.”
To accomplish the goal of acquainting contractors with the new solar pv finance program, Mitsubishi Electric is currently holding training sessions. Mitsubishi is encouraging contractors to visit their website to learn more about the program, and to register for a training session. All authorized Mitsubishi Electric solar contractors are invited to attend, and registration is now open.
A simple solar photovoltaic (PV) system consists of the following basic components:
- A solar cell: A solar cell is a solid-state electrical device (p-n junction) that converts the energy of light directly into electricity (DC) using the photovoltaic effect. A solar cell is categorized as a multi-junction cell, single-junction cell, crystalline cell, thin-film technology, or some of type of emerging PV cell (like organic cells, etc.).
- Solar module: Collections of a single solar cell are termed as solar modules. Solar cells are connected by a wire either in parallel or in series according to the desired output. If we wish to have more current, the cells are connected in parallel, and if we wish to have more voltage, the cells are connected in series.
- Solar module array: When solar modules are connected either in series or in parallel according to the desired output, the collection of the solar module is termed a solar module array.
- Solar charge controller: If we wish to charge the generated DC power from the solar array to a battery, as mostly seen in rooftop installation, a solar charge controller is inevitable. Through this controller, the battery life is elongated and maintains a constant output voltage for the battery input, which is normally either 12 volt or 24 volt. It uses the PWM (pulse width modulator) or MPPT (maximum power point tracker) technique for better charging performance.
- Combiner box: The combiner box is an electrical distribution box where the DC circuit breakers are placed. The combiner box combines the multiple DC inputs coming from the panel (either module or array) terminations and converts these into one DC output. The output of the combiner box is connected to the charge controller or the inverter, depending on the type of system installed.
- Solar array inverter: This inverter is also termed as a central inverter or string inverter. It converts the single DC output power from the combiner box into AC power which then can be connected to the power/electric grid. This inverter uses the MPPT (maximum power point tracker) technique for better optimized output. However, the problem of partial shading or shadowing — technically termed as potential induced degradation (PID) of the solar panel — is prominent with the use of such an inverter.
- Solar module inverter: This inverter is installed at the modular level. It converts the generated DC power to AC power using a micro inverter for each module. This inverter also uses the MPPT (maximum power point tracker) technique for better output. The advantages of an such inverter are that it has more reliability with better performance. And also it reduces the PID effect.
- Power cable: There are two types of power cables. Low-voltage power cables (solar panel to the combiner box, combiner box to the inverter, and inverter to the transformer) and medium-voltage power cables (transformer to the substation).
- Switch gears / protection: Switch gears are one of the most important components in a PV system. It allows protection of the components from any fault during the operation, such as over-current, over-voltage, temperature rises, lightening faults, switching faults, etc. For better reliability of the system, communication between each component is a must. A central monitoring computer allows checking the communication between each component and the execution of tripping the fault.
- Power quality issues: This has become one of the major topics in the utility sector for common consumers. Due to cabling, there is a higher chance for interference in the power signal, which leads to a reduction in generated output power. For such cases, a metal mesh encasing the cables improves shielding. Due to the use of power electronic switches in inverters, common mode (CM) disturbances are prominent. Because of CM disturbances, transience in the power is seen and the output power is distorted. A thorough understanding of EMC related to the PV system is important for better performance and high reliability for that given PV system.
With this basic intro on photovoltaics out of the way, we will next dive into articles more focused on each of these components.
Upsolar yesterday unveiled that it has created new “smart modules” with the help of Tigo Energy. Reportedly, these are the first smart modules to be certified by TÜV Rheinland PTL for Europe and North America. The new smart modules are good for residential, commercial, or utility-scale solar installations.