IEEE Technology and Society Magazine - September 2019 - 49

due to the complexity involved, many programs in the
U.S. are managed by the power company. Ownership of
the infrastructure in a solar community can reside in
the power company, a third party, or the community.
The financing source would determine ownership. The
Solar Electric Power Association and the National
Renewable Energy Laboratory also have guidelines and
models for community-based energy projects. In general, there is a strong emphasis in the U.S. on marketbased alternatives, which evidences the preference
towards reforming traditional utilities in support of
these community-based alternatives. Rural electric
coops and small public power utilities seem to be more
supportive and aligned to community-based and community-led energy initiatives such as solar communities.
Since PR's utility is a public power company, that trend
would indicate solar communities and microgrids would
align well with public power values.
In Puerto Rico, the community-based infrastructure
models that most closely align with community
microgrids are the community-operated water aqueducts that exist in over 200 rural or isolated communities [31], [32]. These communities have their own water
source and water distribution systems. The main lessons from successful community-operated aqueducts
are the need for clear roles, rights, and responsibilities
of all involved, and ample community participation.
Community solar systems have a great potential in
fossil-fuel dependent countries that import their fuels.
Thus, all possible modes of solar communities should
be allowed. However, strategies and models are contextdependent. For example, the cost of residential rooftop PV systems in Puerto Rico is around 11 cents/kWh,
making them financially viable considering that
the residential cost of electricity in Puerto Rico was
21.06 cents/kWh in June 2018 (for the same month the
average U.S. residential price was 13.02 cents/kWh).
Puerto Rico has a competitive rooftop PV market, with
an average cost below $3/W. By comparison as of
August 2018, the average cost of a residential rooftop
PV system in the U.S. was $3.14/W [15]. Since the per
capita GDP in Puerto Rico is about half the per capita
GDP in the U.S., local solar companies must adapt to
this reality and offer prices that are attractive in the
local market. Furthermore, in Puerto Rico there is
strong competition among small to medium local solar
companies, which drives down the overall cost of residential systems. Permitting and labor costs are also
lower in Puerto Rico than in the U.S.
Solar communities should not be viewed only as a
profit mechanism for a few, with minimal community
benefits. Solar communities represent a strategy to
transform the system into a sustainable system, one
that supports local energy solutions. Conservation and
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efficiency programs can also be run within solar communities to ensure the energy resources within the
community cover as much local demand as possible.
Solar communities can be managed to demand nearconstant power from the grid. By matching local energy
resources and the local demand, and ensuring the use
of a block of energy from the utility, solar communities
can be an answer to the limits imposed by the traditional electric infrastructure and can truly achieve the maximum possible use of renewable energy.
A solar community could be transformed into a
microgrid if it had enough local energy resources to
meet the minimum demand. Microgrids are composed
of distributed energy resources and loads that can be
operated independently from the main grid, or connected to it. Microgrids facilitate the use of renewable energy and help to reduce energy losses in transmission and
distribution lines. The IEEE 1547.4 "Guide for Design,
Operation, and Integration of Distributed Resource
Island Systems with Electric Power Systems" and the
IEEE 1547.6 "Recommended Practice for Interconnecting Distributed Resources with Electric Power
Systems Distribution Secondary Networks" provide a
basic framework.
Microgrids can be classified in several ways: by
capacity, by type of generation, and by types of loads,
among other criteria. One of the most common ways
to classify microgrids is by ownership and operational responsibilities.
There are different architectures and control methods for microgrids [16]. The simplest one is within a
customer's premises, with grid connection at one point
that is controlled by the customer. Another topology is
multiple customers fed by a distribution network. In
this type of connection, the point of connection to the
utility grid is usually controlled by the utility. The utility
and the group of customers must come to an agreement as to how the point of connection will be controlled by the utility.
Besides technical challenges, microgrids also need
to overcome social and legal obstacles in order to
become a key component in the transition to a sustainable energy future [17].

Community Perceptions of Solar Communities
UPRM researchers have been working with DERs since
1999, with special emphasis on community-related initiatives. Various capacity building initiatives have included participation from communities [18]. Based on those
experiences, two solar community colloquia were held
in April 2017 in two different cities, with support from
the Center for Grid Engineering Education. About
150 persons participated, representing communities in
northern and southern Puerto Rico. Communities were

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