Grid-Connected Solar Electric System. This renewable energy system contributes to:

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1 Page 2 Pioneer Valley PhotoVoltaics Cooperative Solar Power for Sustainable Communities Grid-Connected Solar Electric System System Guide This renewable energy system contributes to: A brighter energy future Cleaner, healthier air Increased property value

2 Bringing Solar Power Home INDEPENDENT Energy through the power of the Sun. It s here with a reliable, fully-integrated solar system from PV Squared. Finally, property owners can take steps to reduce their dependency on power companies. We are putting the power of the Sun in people s hands. RESPONSIBLE A solar system is one of the most responsible choices concerned property owners can make to protect the environment and help control their electricity budget. Our high-quality, high efficiency solar electric systems use no fossil fuels to produce electricity and generate no pollution. They are safe, clean and quiet. Diversified Construction, 100 University Drive, Amherst, MA Pioneer Valley PhotoVoltaics Cooperative, June 2009

3 Page 4 Introduction: How a Grid-Connected System Works Solar Benefits You and Your World In a world of uncertain energy supplies, rising electricity prices, ecological and health challenges, solar energy is a solution that: Your Photovoltaic System has been designed to provide you with decades of service. With this modern, grid interactive PV system, AC electric power is produced for use at your property and any excess production (more electricity than your property requires at that moment), goes onto the electric utility grid. Contributes to a brighter energy future Utilizing free and non-polluting solar electricity increases your energy independence and lessens your susceptibility to utility rate increases. Creates cleaner, healthier air Your system avoids air emissions, including: Carbon Dioxide 47.5 tons Sulfur Dioxide 175 pounds Nitrogen Oxides 46 pounds Mercury and Other Pollutants (hard to quantify) Based on the current mix of sources used to produce electricity in New England, we estimate that your system will reduce the emission of these pollutants, as detailed in the side panels on the following pages. 1. An array of solar panels converts sunlight to DC electricity. 2. An inverter converts the electricity from DC to AC. 4. Surplus electricity is sold to your utility (a process known as net metering ). 3. Solar electricity powers your property!

4 PV Squared Introduction (continued): Your grid-connected solar electric system takes your property's utility connection and turns it into a twoway path for energy flow. During the day, your solar array may produce more power than your property needs and the excess is sent out onto the electrical grid. At night, the grid provides power to your property. Power flowing in either direction is measured by your utility meter ( net meter ) and you are credited for the power you provide to the utility. Thus some of your electric power comes to you each month directly from the sun. As a result, you receive a smaller electric bill from your electric utility company each month. Page 5 Your System: Reducing Air Pollution 1: Greenhouse Gas Emissions An Estimated Annual Reduction of 47.4 Tons of Carbon Dioxide By changing the atmospheric concentration of greenhouse gases, we risk creating widespread damage to the environment. There is general agreement among scientists that climate change is due to the emission of greenhouse gases, and that all nations must take action to reduce the release of these gases.

5 Page 6 Photovoltaic System Your System: Reducing Air Pollution While predicting the progression of these changes is difficult, the effects are already measurable. Snow cover in the Northern Hemisphere and sea ice in the Arctic Ocean have decreased. Globally, sea level has risen 4-8 inches over the past century. Worldwide precipitation over land has increased by about one percent. The frequency of extreme rainfall events has increased throughout much of the United States. Fossil fuels burned to run cars and trucks, heat homes and businesses, and power factories are responsible for about 98% of the United States carbon dioxide emissions. In 1997, the United States was responsible for about one-fifth of the total global release of greenhouse gases. 2: Estimated Annual Reduction of 175 Pounds of Sulfur Dioxide Sulfur Dioxide is a colorless gas with a sharp, irritating odor. It is produced from the burning of fossil fuels (coal and oil) and the smelting of mineral ores that contain sulfur. Sulfur dioxide can irritate our eyes, affect the respiratory system, and damage the lungs. When sulfur dioxide irritates the respiratory tract it causes coughing and aggravates conditions such as asthma and Photovoltaic Array: Your array of 420 Sanyo 195 watt photovoltaic modules provides your property with electric power, conditioned by an inverter assembly. We estimate the power production of your system by analyzing the orientation of the array, the expected performance of the modules, the expected performance of other parts of your system, shading, and climate data (using standards set for our industry). Array Tilt Array Tilt = 10º Array Azimuth Summer Black Arrow : Magnetic North (showing declination) Red: 180º Solar South Blue: 180º Your Array Fall/Spring Winter Your Array Tilt = 10º Your Array Azimuth = 180º For your installation in Massachusetts, magnetic South differs from solar South by about 14 degrees. This difference in angle is called declination.

6 PV Squared Photovoltaic Array (continued): Following industry standards, your PV modules are rated to produce 195 Watts each under Standard Test Conditions (STC) and an array of 420 modules to produce 81,900 Watts total of power STC. This gives your system a nameplate value of 81.9 kilowatts (kw) and this is the common shorthand used to talk about the power potential of your system. Based on panel orientation, additional engineering data and site specific conditions, we expect the energy production from your photovoltaic system to be about 86,097 per year* (as a long-term average). Energy usage and production vary throughout the year. Energy production is highest in the Summer months and lowest in the Winter months. This is primarily due to the duration of sunlight each day, and to a lesser extent, due to the seasonal change in the Sun s angle. * this projected output is not a performance guarantee. Page 7 Your System: Reducing Air Pollution chronic bronchitis and can make people more prone to respiratory tract infections. Sulfur dioxide can attach itself to particles and, if these particles are inhaled, can cause more serious effects. 3: Estimated Annual Reduction of 46 Pounds of Nitrogen Oxides Nitrogen Oxides are a group of highly reactive gases, all of which contain nitrogen and oxygen in varying amounts. Many nitrogen oxides are colorless and odorless. However, one common form, nitrogen dioxide (NO 2 ), along with particles in the air, is often seen as a reddish-brown haze over many urban areas. Nitrogen oxides form when fuel is burned at high temperatures, as in a combustion process. Man made sources include motor vehicles, electric utilities, and other industrial, commercial, and residential sources.

7 Page 8 Your System: Reducing Production of Hard-to- Quantify Pollutants Photovoltaic Array (continued): 4: Particulates Coal ash Mercury Nuclear Waste Your system also reduces the production of particulate matter, coal ash, mercury, and other by-products of conventional coal generated electricity. In addition, it reduces the need for electricity from nuclear power generation, with its associated (and largely unsolved) issues of isolating high- and low-level nuclear waste from the environment. Although difficult to quantify, your PV system does reduce the volume of these wastes, and the problems associated with them. Preventive Maintenance Normal rain and snow events keep the panels clean; only in very rare circumstances would you need to consider cleaning the panels. That said, the array works best when free of any obstruction. The panels may be washed if dirty or obstructed (e.g., by snow, bird feces, seasonal dust, etc.), with water or a soft mop. Be gentle when cleaning so as to avoid scratching the glass surface. We recommend that you annually conduct a visual inspection to ensure that the wiring on the roof has not been damaged by squirrels or by other rodents. Ninety-three million miles out in space is the best energy source on earth, the sun a vast engine that showers us with 1.5 quadrillion megawatt hours of energy each year and supplies enough power every minute to meet the annual needs of the entire world. John Schaeffer WARNING: The components of your system should only be worked on by a qualified electrician or PV Squared technician. Even the electricity carried on the DC side of your system is dangerous, due to high voltage and high current. It is not like the DC power you may be familiar with in small household electronics. It is hazardous if not handled correctly, and can cause electric shock, burns, or death. Only a PV Squared technician should work on these components.

8 PV Squared Page 9 Inverter: While your PV array is the silent workhorse of your PV system, your inverter is the brain that controls the power and its flow. It converts the direct current (DC) electricity from the PV modules into grid-ready alternating current (AC) electricity and it constantly monitors grid power to ensure your PV system is properly matching its power output to that of the grid. Inverter LED s The inverters LED s shows different modes of operation. These LED s indicate the status of the inverter. See the Inverter manual for specific LED indicators For in-depth operation instructions for your inverter, see the inverter users manual. Preventive Maintenance The inverter unit is fully automatic and should operate for years maintenance-free. Do not cover or clog air vents or store anything on top of the unit. This will increase the temperature of the unit and reduce the performance of the inverter.

9 Page 10 Meters and Other System Components: Since the commissioning of your system, the system output (in kilowatt-hours) is recorded by your system production meter. Your system production meter is utility grade, for accuracy in reporting production. Your utility meter (net meter) keeps track of your imported grid power and excess PV production. Your electric utility owns the net meter and is responsible for its maintenance. Other Electrical Components The photovoltaic system has several electrical junction and disconnect boxes, and electrical conduit necessary for interconnection of components. Preventive Maintenance Electrical junction and disconnect boxes should always remain closed. Outdoor components of the system should be visually inspected annually. Indoor components may be inspected every few years. While this inspection of meters and electrical connection components is recommended, these components are unlikely to require maintenance or to become a source of problems.

10 PV Squared Page 11 System Components and Flow of Energy: As illustrated here and discussed throughout this user s guide, electricity generated by your PV array travels through your system via the following paths. Blue arrows indicate flow of energy PV Array Load Center Utility Meter Fused Combiner Boxes Inverter Production Meter

11 Page 12 Operation How do I know if my grid-connected solar electric system is working correctly? Whenever the Sun shines, your DC to AC inverter operates automatically without user interaction and without maintenance. The inverter switches into a standby mode whenever there is insufficient DC electricity available to produce the grid-ready AC power (output). For example, the inverter switches to standby when solar radiation to the PV panels decreases each evening. The next day, the inverter automatically starts up once the morning solar radiation is strong enough to wake the inverter. Therefore the inverter is either in operation or on standby and always ready when incoming solar radiation is sufficient to produce power. Each time the inverter starts up, it runs a number of internal self tests and safety procedures. In normal operation mode, the Green LED light is on. The inverter is supplying power to your property and at times to the local electricity grid. Additionally the inverter display will show information about power production and operating status.

12 PV Squared Renewable Energy Certificates & Green Tags Page 19 Renewable Energy Certificates (RECs), also known as Green Tags, Renewable Energy Credits, or Tradable Renewable Certificates (TRCs), are the property rights to the environmental benefits from generating electricity from renewable energy sources, such as solar power. RECs represent a kind of currency; they can be bought, sold, and traded. RECs are an incentive for users to create clean, renewable energy by providing a subsidy to electricity generated from renewable sources. As a clean energy system owner, you can realize an additional economic benefit from your system s production by selling your RECs into this emerging market. PV Squared supports having system owners sell their RECs, because such transactions directly benefit the owner while serving to encourage further development of clean energy technologies and their deployment. clean energy generator electricity RECs A 5 kw photovoltaic system, generating in our region about 6,000 kwh each year, avoids the conventional generation of an equivalent amount of electricity and its associated pollution products. Considering just atmospheric emissions, this amounts to preventing the emission of 13 pounds of sulfur dioxide, 3.4 pounds of nitrogen oxides, and 6,900 pounds (nearly 3.5 tons!) of carbon dioxide. Other pollution is similarly avoided; such as emissions of compounds of ash, mercury and other particulate matter, land and water quality degradation, and high and lowlevel nuclear waste.

13 Page 20 Renewable Energy Certificates & Green Tags (Continued): A clean energy source (such as a PV system or wind farm) is credited with one REC for every 1,000 kwh of electricity it produces. A certifying agency gives each REC a unique identification number to make sure it doesn't get double-counted. The electric energy is fed into the grid (by mandate), and the accompanying REC can then be sold on the open market. For example, a 5 kw photovoltaic system operating in your region can be expected to generate approximately 6,000 kwh of electricity and produce a corresponding 6 RECs in a typical year. If the system owner were to sell his or her RECs for to use a simple hypothetical example -- $10 per REC, the 6,000 kwh converts to six RECs, and the system owner receives $60. On the demand side, an average residential customer consumes about 6,000-9,000 kwh in a year. If this customer chooses one of the green electricity options with the utility company, she/he automatically buys six to nine RECs and retires them from the market. The buyer of RECs can legally claim to have purchased renewable energy. The owners of small PV systems usually sell their RECs to a broker under a multi-year contract. This might involve the owner reporting the system s production quarterly to the buyer, who in turn sells RECs in large aggregate blocks to utilities and other corporations. PV Squared is prepared to help clean energy system owners connect with REC brokers. We have no business connection with them. Electric utility companies routinely buy large quantities of RECs, because they are legally required to purchase or produce renewable energy as a component of their mix of generating sources. Other REC buyers include companies who are then able to offer green electricity to retail residential, commercial and other electric customers. While the market for RECs cannot be characterized as mature at this time, this should not prevent you from entering this emerging market to realize an additional benefit from your clean energy system.