Solar, the Fair-Haired Boy
Solar photovoltaic (PV) is a light-based technology well known and
embraced throughout the world. Its popularity is pretty obvious: install
these modern marvels and generate your own electricity. The US and New York State governments, among others, offer income
tax credits to offset the installation costs and electric utilities or
power authorities often provide rebates to encourage their use, provided
they are tied into the electric grid.
As a result, more and more people
are going solar, whether via outright purchasing or through financing
plans, leasing or power purchase agreements (PPA). When PV systems are grid-tied, these on-site power systems become
distributed generation (DG) sources, which reduce the strain on
distribution systems and add resiliency to the grid. Electricity
produced but not used is exported to the grid and used as a credit
against future electric use. This ensures customers are charged only for
their net energy use at the end of the monthly billing cycle. Most
often net metering allows credits to be rolled over from month to month
with any residual credits being settled annually. Some states’ utilities
settle the credits on a retail basis, others on an avoided cost basis.
Net-metering is a great innovation, since PV systems, when in
operation, often produce more than a home can use at a given time,
particularly during midday hours. Without storage and net-metering, this
energy would be lost. When the system is not in operation, such as
nighttime, the home can draw power from the grid as needed. On average,
20-40% of a solar energy system’s output is exported (SEIA).
The Solar Energy Industries Association (SEIA) points out “…net
metering policies create a smoother demand curve for electricity and
allow utilities to better manage their peak electricity loads.” (SEIA)
There are other, less obvious community-wide benefits. When the
unused electricity is sent out over the electric grid it goes to the
utility’s local power distribution system, which redirects this
electricity to nearby customers’ homes. This means the entire community
can gain from some members’ solar PV system’s output.
The electricity from these DG sources is stored by a variety of
small, grid-connected devices called distributed energy resources (DER).
A smart grid can manage and coordinate DERs within it. This is one of
the reasons DERs are playing an increasingly important role for the
grid, even though their capacities are tiny in comparison with
centralized commercial power plants.
Having many small, modular local power stations are more flexible
than conventional power plants, while long-distance transmission from
them can cause about a 10% energy loss (SEIA). Localized power generation and storage allows the collection of
energy from many sources resulting in greater the security of the energy
supply. This diversity may also lower the environmental impacts of our
way of living.
Going solar has become more a question of when not why.
There is no way our society can survive and thrive without generating
electricity with renewables. It is the way of the future in powering all
our appliances in home, office, factory and school. But solar is only one half of the renewable energy
equation… Solar may power our appliances, but how do we heat without
fire? Can we efficiently heat indoor spaces with technologies that use
electricity?
http://blog.renewableenergyworld.com/ugc/blogs/2015/09/why_the_solar_pvind.html
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