The most common solar technologies used on buildings in the United States are solar photovoltaic (PV) panels, which generate electricity. An individual PV cell is usually small, typically producing about one or two watts of power. To boost the power output of PV cells, they are connected together to form larger units, called modules. Modules, in turn, can be connected to form even larger units, called arrays, which can be interconnected to produce more power, and so on. Because of this modularity, solar PV can be designed to meet any electrical requirement, no matter how large or how small.

SOLAR POWER BASICS

Modules or arrays do not complete an entire system. Structures that point them toward the sun and components that take the direct-current electricity produced by modules and “condition” that electricity, usually by converting it to alternate-current electricity, are also part of a solar energy system. These items are referred to as the balance of system (BOS) components. Combining modules with BOS components creates an entire system.

The majority of solar PV systems are grid-tied. This means they are directly connected to the power grid and do not require battery storage. Solar PV systems will not operate during a power outage unless it has battery backup. Solar electrical energy can provide power to a home or business, reducing the amount of power required from the utility. When the solar PV system power generation exceeds the power needs at the home or business, then the surplus power automatically back feeds into the grid. A special utility meter will record the “net” power coming in from the utility and the surplus power flowing out from the solar PV system. Solar PV systems can be installed on a roof, integrated into a building or roof structure, or ground mounted on poles or racks. Tracking systems on poles can enable the modules to follow the sun during the course of the day to increase the overall output of a solar PV system.

SOLAR IN ACTIONThere are three basic types of solar voltaic systems:

Off-Grid An off-grid system is designed around the estimated electrical load consumption both with production (solar array) and storage (batteries). It involves solar modules (array), solar charge controllers, batteries, and inverters (DC-AC power conversion). Most off-grid systems incorporate a generator for backup. The generator can be configured to automatically start when needed.

Grid-Tie A grid-tie system does not use batteries and does not provide utility backup. It involves a solar array which generates DC power during the day which is converted to AC by an inverter and sent into the house side of the electrical meter. If the home is using less power than the system is generating the electricity flows out the meter (spinning it backwards) to the grid. A grid-tie system will reduce your power bill by the amount of kWhs produced and is the least expensive pv system choice.

Grid-Tie with Backup A grid-tie/backup system is essentially a combination of a grid-tie and an off-grid system. It uses a similar inverter to the off-grid systems and incorporates a battery bank. It back feeds power either to the house loads or to the grid like a grid-tie system but in the event of a grid power outage it can provide backup power to designated critical loads.

BENEFITS OF SOLAR

“Every hour, enough solar energy strikes the earth to power all human activities for over a year. Solar is reliable, clean, cheap, abundant, versatile, domestic, and safe.” - National Association of Regional Councils

SOLAR PV TECHNOLOGIES ARE RAPIDLY IMPROVING They have been around for 50 years, with current systems able to reliably produce affordable energy for 25-30 years.

SOLAR IS FLEXIBLE It can be swiftly deployed and can provide significant amounts of reliable electricity during periods of peak energy use on the electric grid.

SOLAR IS AFFORDABLE In some regions, the cost of solar is cheaper than traditional energy sources.

SOLAR IS CLEAN It generates just 0.07-0.2 pounds of CO2 per kWh (as compared to traditional sources: coal generates 2.14, natural gas generates 1.22 pounds of CO2 per kWh).

SOLAR IS SAFE It has minimal installation risk when compared to mining, nuclear generation, or oil drilling and transport.

ECONOMIC BENEFITS The U.S. solar industry employed 260,077 workers in 2016, a nearly 25% increase in the number of jobs from 2015. That jump was largely driven by a massive increase in solar panel installations. Workers who install rooftop solar panels make up the largest share employment in the sector at 137,133 jobs. Manufacturing is a distant second with 38,121 jobs, followed by 34,400 in project development, and 32,147 in sales and distribution Companies looking to expand may be more likely to consider regions with “solar-friendly” regulations and processes.

ENERGY PRICE STABILITY Having solar as a component of a region’s energy portfolio provides energy price stability both for an individual property owner and on a regional scale. After the upfront investment in solar, costs are predictable. In addition, solar performs best during peak energy use hours (i.e., 4:00pm-6:00pm, on average) when power produced by traditional sources is most expensive, and at highest risk of being overloaded. For a utility, the more customers are able to use solar during peak usage times, the less burden it imposes on the utility’s generation and transmission capacity. This allows for more predictability with the utility’s costs. This type of cost certainty is becoming more valuable as traditional energy costs become more volatile.

SMART INVESTMENT Solar is a smart investment for local governments, homeowners, and businesses. In addition to the potential energy cost savings for the homeowner, recent research shows that “home buyers consistently have been willing to pay more for homes with host-owned solar photovoltaic (PV) energy systems--averaging about $4 per watt of PV installed--across various states, housing and PV markets, and home types. These cost savings are enticing businesses as well, especially those with hundreds of acres of available rooftop real estate. In addition, schools and governments often have prime solar real estate on municipal buildings with large rooftops or on underutilized land like capped landfills and brownfields. Returning these sites to productive economic use can generate significant revenues for a municipality.

PLANNING FOR SOLARThe first step in planning for solar is often removing local zoning code barriers that inadvertently make solar systems difficult to install, followed by adopting facilitating codes and ordinances, and enabling solar access in new developments. When communities address solar energy systems in development regulations they may be defined these systems as accessory structures, accessory uses, or primary uses. Potential conflicts can arise, with tradeoffs between system optimization and aesthetic effects on surrounding properties. Some communities permit accessory solar energy systems by right in all zoning districts, while others have special permitting processes that take into account site design and potential impacts to adjacent property owners. Relatively few local governments address large-scale solar installations (i.e., solar farms) in development regulations because utility-scale solar projects are typically subject to state or federal review as part of the permitting process. However, a growing number of communities are identifying large-scale solar installations as a land use. Typically permitted as conditional uses in a limited number of industrial or agricultural zoning districts and may be subject to specific use standards to address potential impacts.

College Township has adopted a Solar Energy Systems Ordinance, and Patton Township is in the process of adopting a similar ordinance.

SOLAR IN PENNSYLVANIAThe United States is among the top five countries leadiing the world in solar energy, at (5) with 18,317 MW of overall capacity. The other leaders are (1) Germany, 38,250 MW, (2) China, 28,330 MW, (3) Japan, 23,409 MW, and (4) Italy, 18, 622 MW.

Pennsylvania is home to more than 514 solar businesses, making it one of the largest solar employers in the nation, ranked at number four. 6,000 green solar energy systems have been installed. Not only have these efforts yielded about 5,000 green jobs in the state but also it has allowed the state to generate three times more solar energy than what is required by Pennsylvania law.

The map shows that the amount of solar irradiation, or solar resource available to the continental United States is greater than that of Germany, the world leader in solar capacity.

Cumberland County - Carlisle Area School District & Cumberland Valley School District (1 MW system each)

Two of the largest solar power systems in Cumberland County are owned by local school districts. Both the Carlisle Area School District and the Cumberland Valley School District each operate a 1 MW solar system, providing each school district with clean, cheap energy from the sun. Carlisle’s system generates 16% of the District’s entire energy needs, while CVSD’s utility costs were cut 15% by their solar system.

SOLAR IN PENNSYLVANIALancaster County - Masonic Villages Retirement Community in Elizabethtown, PA (1 MW)

Built in 2011, the solar farm at Masonic Villages Retirement Community provides 5% of the energy the community uses. The system, located on 5 acres of the property, is the largest solar system at a continuing-care retirement community in Pennsylvania.

York County - Snyder’s-Lance in Hanover, PA (3.5 MW)

Completed in May of 2011, the 3.5 MW solar system across the street from the headquarters of Snyder’s-Lance was for a time the largest ground-based solar farm in Pennsylvania. Overall, this solar system was designed to produce 30% of the energy needs for the headquarters and manufacturing facility.

Northampton County - Crayola Solar Farm in Easton, PA (1.9 MW)

The largest solar farm in Northampton County provides clean solar energy to the Crayola factory just outside of Easton, PA. The 30,000 panels in this solar farm generates enough power for Crayola to make 1 billion crayons and 500 million markers every year.

Philadelphia County - Lincoln Financial Field (3 MW)

The Linc, home of the Philadelphia Eagles and Temple Football, added a $30 million renewable power upgrade in 2010. This system, which features more than 11,000 solar panels installed on carports, the stadium roof, and vertically mounted on the stadium’s exterior, is the largest in the NFL with a 3 MW peak production capacity.

Allegheny County - PA Solar Park (11.5 MW)

The PA Solar Park, covering 55 acres in Nesquehoning, PA, is a solar array operated by the Con Edison utility. It features over 39,000 panels with a generating capacity of 11.5 MW. Phase II of the project, currently under construction, will nearly double the generating capacity of this facility to 20 MW.

Sources: American Planning Association, Delaware Valley Regional Planning Commission, SunShot, US Dept of Energy, PA DEP/Solar, US Green Technology Working Group, Solar Energy Installers Association, Sundance Solar Systems, National Association of RegionalCouncils, Meister Consultants, College Township, PennFuture

SOLAR IN PENNSYLVANIA