Solar photovoltaics (solar PV) convert sunlight into electrical energy
through an array of solar panels that connect to a building's
electrical system and/or the electrical grid. Below, you’ll find an
overview of the important policies and topics one should understand
when thinking about installing solar PV. Solar PV in Massachusetts
Massachusetts is known as a national leader in solar energy and one of
the best regulatory and incentive climates for solar energy. Since
2007, the number of solar installers in Massachusetts has grown from
50 to more than 270, and the Massachusetts solar market has enticed
numerous businesses that offer innovative financing models that aim to
make solar energy accessible for more people in the Commonwealth. For
more information on how to find and compare installers, please see our
Finding a Solar PV Installer page. For more information on solar
financing models, please see the Clean Energy States Alliance
Homeowner's Guide to Solar Financing. Equipment Basics A solar PV
system consists of a few pieces of equipment wired together and
connected to a home’s or building's power distribution network.
Components typically include: Solar PV Array: When sunlight strikes
the semiconductor material inside a solar cell, it frees electrons,
which are then captured in an electric current. This process
converts sunlight directly into electricity. The more intense the
sunlight striking the cell, the greater the amount of electricity
produced. Solar cells are aggregated together to form a PV panel or
a module. A solar array generally includes several modules wired
together to achieve the desired system capacity or power producing
capability. Inverter: Solar PV panels produce direct current (DC)
power, which must be converted to alternating current (AC) power which
is supplied by electric utilities in the United States. This is
accomplished by an inverter. Typically, the inverter is located near
where the electric service from the local utility enters the house
(close to the electrical panel). In grid-connected systems, inverters
are designed so that if power from the utility goes down, the PV
system will shut down as well. This is an important safety precaution
for utility workers, and the PV system will not restart until power
has been restored to the grid. Shut-Off: Some Massachusetts utilities
require an external shut off, or a disconnect, for the PV system so
that the power company can shut down the system if necessary when
workers are fixing the power lines. Visit energysavers.gov for
detailed information on this and other clean energy technologies.
Economics of Solar PV Massachusetts’ vibrant solar industry has a
variety of ownership and financing options for residents and
businesses looking to install solar PV in the Commonwealth. These
options include direct ownership, solar leases, or power purchase
agreement (PPA) contracts, in which a homeowner purchases solar energy
from a system located on their property. Consumers should thoroughly
review any solar PV financial arrangement. Below is an overview of
some of the costs and benefits one should understand before signing a
contract to install solar PV. Aside from the various incentives a
system may qualify for, it is important to note that the cost-benefit
analysis regarding solar PV is site specific and should include an
analysis of a particular site’s shading, orientation and roof pitch,
as well as the solar PV equipment’s efficiency, customer's electric
rates, and other factors. Upfront Costs and Incentives Purchasing a
solar PV system generally requires upfront installation and equipment
costs, but there are significant benefits that are realized over time.
Upfront costs can be offset by the following: Federal Tax Credit –
A 30% federal Investment Tax Credit (ITC) for qualified residential
and commercial projects Massachusetts Personal Income Tax Credit –
The lesser of 15% of the total cost of the PV system or $1,000, for
qualified clean energy projects Modified Accelerated Cost Recovery
System (MACRS) - Accelerated depreciation is available for eligible
commercial projects For more information on incentives that are
offered for clean energy projects, please visit MassCEC’s Financing
Clean Energy Projects page, or the Database of State Incentives for
Renewables and Efficiency (DSIRE). Long Term Costs and Incentives
Solar PV system owners will also realize long term economic benefits
such as: Avoided Electricity Costs: Solar PV owners can utilize the
electricity produced by their system to directly offset their
electricity load. Solar Renewable Energy Certificates: Solar PV owners
can generate income from the sale of Solar Renewable Energy
Certificates (SRECs), which are the positive environmental attribute
of the clean energy produced by a solar PV system. These are tradable
certificates based on the production from your solar PV system. The
Massachusetts Department of Energy Resources (DOER) qualifies eligible
solar projects, allowing the owner to begin selling their generated
SRECs in the market. This creates a way to obtain long-term financing
for your solar PV system. For more information, visit DOER's About
the RPS Solar Carve-Out II Program web page or the RPS Solar
Carve-Out II Program Overview. Net Metering: Net metering is a state
regulation that allows customers generating their own electricity to
be credited at nearly the retail rate for the energy they generate but
do not use. A customer’s electric meter will run backward whenever
the home or building is producing more solar power than is being
consumed, and their utility account gets net metering credits for net
excess generation at the end of the monthly billing period. For more
information on net metering and interconnection, please visit
DOER's Massachusetts DG and Interconnection web site. As is the case
with any appliance, solar PV systems require some maintenance over
their lifetime. This generally includes making sure the solar panels
are clean, ensuring the panels are receiving unobstructed sunlight,
and replacing the inverter generally once during the life of the solar
PV project, which should be between 20 to 25 years. Installers should
provide a minimum five-year labor warranty to protect your equipment
against defective workmanship, PV component breakdown, or significant
degradation in electrical output. In addition, the solar PV equipment
should have appropriate manufacturer’s warranties.