The ideal roof is a south-facing, slanted roof with no shading on the area where the modules will be located. PV can be installed on east and west roofs, but the efficiency may be lower. Please call BPVS to discuss your buildings details and a site assessment.

28 degrees is the optimal tilt for year round performance. It is important to note that the difference exhibited while varying module inclinations between 5 and 30 degrees is not more than 8%, and between 17 and 45 degrees (covering the range for most residential roofs), you will make use of 98-100% of all available sunlight. BPVS will take all factors into account when we design your system and will work with you to arrive at the system design that is truly optimal. 

1 kW of Panasonic, very efficient, solar modules will occupy an area of approximately 69 square feet. This module is ~ 72 inches tall by 40 inches wide.

Yes, A system rated at 2 kW will produce about 2,400 kWh annually. This is enough to provide one quarter of the average New England home’s electricity. For homes with efficient appliances and lighting, and conservative energy users, a 2 kW system may provide much more of the energy than the household needs. Because New England uses more energy in summer time when photovoltaic production is at its peak, the clean electricity produced by grid-connected systems is especially valuable.

A 1 kW PV array installed optimally in Massachusetts should produce on the order of 1,200 kWh per year from 20 year meteorological averages. Our Berkshire customers have averaged 1158 kWh per year per kW in the past four years.

PV clean energy displaces the carbon dioxide, nitrogen oxide, sulfur dioxide, mercury and heavy metal particulates that result from burning fossil fuels to generate electricity. A PV system in our region produces best in summer when grid electricity demands are highest and when the dirtiest power plants are in peak operation. In Massachusetts every solar kilowatt hour defers on average about 0.72 lbs. of Co2 , 0.0001 grams of Sulfur Dioxide, 0.0005 grams of Nitrogen Oxides, and 0.0002 mg of Mercury.

Small, rooftop Residential PV installations are more expensive per kW than larger residential systems. A lot can depend on the quality and material of the roof, mounting system (roof, ground, pole), and permitting costs. Commercial and institutional systems are typically lower per kW due to economies of scale. We favor environmentally responsible manufacturers with ultrapure silicon production in house or from a reputable supplier, financial depth and proven warranty assurances. The energy needed to manufacture the PV modules installed by BPVS will be reclaimed within the first fourteen months of their operation for those concerned with embedded costs. When we examine the external costs to the environment and to future generations for conventional power, PV is a bargain.

No. If you are not connected to the grid, you can use what is called a stand-alone PV system. This includes a battery bank to store energy for use at night and cloudy days. BPVS is a recognized leader in stand-alone design and installation. PV is versatile, so stand- alone systems may power a full size remote home or a single water pump in a remote pasture.