Solar power is the conversion of sunlight to electricity. Sunlight can be converted directly into electricity using photovoltaics (PV), Photovoltaics were initially used to power small and medium-sized applications, from the calculator powered by a single solar cell to off-grid homes powered by a photovoltaic array.
A solar cell, or photovoltaic cell (PV), is a device that converts light into electric current using the photoelectric effect. There are many competing technologies, including at least fourteen types of photovoltaic cells, such as thin film, monocrystalline silicon, polycrystalline silicon, and amorphous cells, as well as multiple types of concentrating solar power.
Solar photo-voltaic (PV) technology is the way of the future, for generating and supplying electric power for homes and businesses in the US and across the world.
The only thing holding back the wide-spread application of solar PV is the long return on investment that in some situations may exceed 10 years. Fortunately, the US federal government and local and state governments have many incentives and rebate programs for solar energy projects.
Environmental Solar Systems is partnering with Enphase energy to simplify and improve on your residential photovoltaic experience. The breakthrough Enphase Microinverter System is making solar power systems more productive and far more reliable.
The system consists of three components:
The Microinverter that attaches to the racking beneath each solar module and converts DC power to grid-compliant AC power
The Envoy Communications Gateway (EMU) that collects and transmits performance information from each solar module to a proprietary website for use by the customer
The Enlighten website where Enphase customers can monitor and manage their solar power systems 24 hours a day
The Enphase Energy Microinverter system is a set of small units that connect directly to each solar module to convert DC power into grid-compliant AC power, and transmits valuable performance data on each module to the system owner. The result is more power, a more reliable system, and the ability to monitor and respond quickly to performance issues. Home owners and business owners get more energy, lower costs, and greater control of their solar investment.
The Enphase Energy Microinverter system is:
Per-module tracking makes system more productive
Increased system up-time
Increases resilience to shade, dust and debris
High conversion efficiency
Greater production in low-light conditions
No single point of failure
Reduced component stress
Very low internal temperature rise
Designed to NEMA 6 rating
24/7 monitoring on a per-module basis
Eliminates the space, heat, and noise issues of a large inverter
Dramatically reduced installation design
Modules can be mis-matched and added as requirements change
Modules do not need to be collocated
Transparent Installation and Operation
When the Sreenivas family needed a new roof, they decided to install solar power at the same time. Concerned about the aesthetic beauty of their home, they wanted the installation to impact their property as little as possible. When reviewing design options, the family was concerned that a system with a centralized inverter would be visually intrusive, dangerous for children, and clutter their property with cables, wires, and boxes.
The Microinverter Difference
Installers Borrego Solar Systems presented the Sreenivas family with a solution using the Enphase Microinverters. Microinverters are installed beneath the solar modules, thereby hiding them from view. This would eliminate the need for – and potential danger of – a central inverter, reduce the amount of cabling and wiring routed through their home, and leave the solar modules as the only visible hardware on their property. The Enphase Microinverters are completely silent, thereby reducing any further disruption to their home life. In addition, the Enlighten website allows the family to monitor their power production and usage, providing peace of mind that the system is operating as expected.
The family chose the Enphase Microinverter System for their solar power installation. The installation took place in a few days and the entire experience had minimal impact on the family.
Minimal additional equipment
No impact on visual beauty of home and property
Peace of mind with 24 hour monitoring
How do I know if a solar PV system from Environmental Solar Systems is right for me?
Step 1 – determine if your site can accommodate a solar photovoltaic system
Southern Exposure: Solar PV systems operate by converting sunlight into electricity, so the first thing they require is enough sunlight throughout the year, with as little obstruction or shading as possible. If you plan to use a solar system that will be fixed (usually a roof mounted solar array), you will need to position it so that it faces south and is not in a shady location.
Angle or slope for solar panels: Depending on where you live or plan to install your solar system, an angle or incline of the panels may have a significant effect on electricity production. Here in New England the sun is at about 20 degrees to the earth’s surface during the winter and at about 45-50 degrees during the summer. If you plan to have a fixed solar systems installed in MA the ideal angle for your panels would be 30-32 degrees.
Size of your roof: If you plan to have a ground-mounted solar system, this will be irrelevant as there is usually enough room to have a decent size system installed. If you plan to have solar panels installed on your roof, depending on the number of kilowatts you plan your future solar system to be, you may need a considerable roof area.
Step 2 – figuring out the size (in Watts) of your future Solar PV System:
How many Kilowatts do I need?
This will surprise many people, but solar PV systems are priced in Watts or Kw – NOT in Sq. Ft. Solar electricity production depends on how many “sun-hour-days” you have in your area. In Massachusetts and surrounding states (Connecticut, Rhode Island, Southern NY) we have an average of 4.2 – 4.5 hours of sunlight (sun hours) per day annually. This accounts for rainy and cloudy days as well as long, sunny summer days and short winter days.
Most households in the US consume on average 750 kWh (kilowatt-hours) per month. Assuming a 4.5 sun-hour-day in your area, a 1 Kilowatt solar PV system should produce 4.5 kilowatt-hours of DC electricity per day. Per month it will produce 135 kWh DC. This DC electric current has to be converted to AC, so that your home appliances can use it. The micro inverters from Enphase take care of this part, as well as optimizing the functionality of your solar panels.
To become completely independent from your utility company you will need to produce about 750 kWh of AC electricity. With 4.5 sun-hour-days you will need 6 kW solar PV array which is optimally designed and is placed in an optimal location – no shading, perfect angle, etc. This is the best case scenario.
An average residential solar installation is 2-4 kW system which usually eliminates 50-70% of electric power that you purchase. However those installations are still dependent on additional electricity
National average cost to install a solar PV system ranges from $9 to $12 per watt or $9000-12000 per kW DC (direct current) of solar system installed, with smaller installations being at the top for this price range due to fixed costs such as equipment, setup, installation, permits and paperwork.
The most expensive component of the solar PV system is the solar panels themselves, however, equipment such as the microinverters (which convert DC into AC and feeds it into your meter) also add to the cost of a smaller size PV systems. Therefore for a 3 kW residential solar system, the cost will be around $11 per watt or $33000 total system cost when using conventional solar panels.
Fortunately the $33000 price tag is not your actual cost, as there are federal tax credits available as well as a wide range of rebates for solar PV installations here in Massachusetts.
For residential Solar PV systems, the Federal Tax Credit is 30% percent with $2000 cap.
Building on the success of the Commonwealth Solar rebate program, which issued awards for 23.5 megawatts (MW) of solar power in less than two years, the state of Massachusetts has issued new rebate programs that continue the momentum toward Governor Deval Patrick’s goal of 250 MW of solar energy installed by 2017.
Beginning in January 2010 the new programs—Commonwealth Solar II and Commonwealth Solar Stimulus—began accemting applications for these solar photovoltaic (PV) systems. The application process, award requirements and forms are under development and are available here
The proposed rebate levels for each program are set and are shown below.
The program funding for Commonwealth Solar II, which will provide rebates for photovoltaic (PV) systems which are 5 kilowatts or less (residential and small commercial systems), will come from $1 million per quarter in existing funds of the Massachusetts Renewable Energy Trust. As part of the Patrick-Murray Administration’s Massachusetts Recovery Plan to secure the state’s economic future, the program funding for Commonwealth Solar Stimulus, which will provide rebates for commercial PV systems sized greater than 5 kilowatts (kW) up to 200 kW, will come from $8 million in State Energy Program funding from the federal American Recovery and Reinvestment Act.
These new rebates are specifically targeted to complement and support the introduction of the new Solar Credit market in Massachusetts in January 2010, which is being developed by the DOER under the state’s Renewable Portfolio Standard. Rebate recipients under Commonwealth Solar II or Commonwealth Solar Stimulus will additionally be able to participate in the Solar Credit market. The Solar Credit market will be an important and sustainable part of building predictable market support for the solar industry in Massachusetts. More information about the Solar Credit Market is on DOER’s website at www.mass.gov/doer.