Microgrids and Community Energy Projects: Distributed Generation for
the (Currently) Limited Niche Markets of Off Grid Backup Power, Closer-to-Usage
Applications, Meeting RPSs, and Solar Investment for Those without Ideal
Rooftop Access
A microgrid is defined at Wikipedia as:
“a localized grouping
of electricity sources and loads that normally operates connected to and
synchronous with the traditional centralized electrical grid (macrogrid), but
can disconnect and function autonomously as physical and/or economic conditions
dictate.”
They also give another definition from the U.S. DOE
Microgrid Exchange Group:
“A microgrid is a group of interconnected loads and
distributed energy resources within clearly defined electrical boundaries that
acts as a single controllable entity with respect to the grid. A microgrid can
connect and disconnect from the grid to enable it to operate in both
grid-connected or island-mode.”
Another DOE definition
“a distribution network that incorporates a variety of
possible DER that can be optimized and aggregated into a single system that can
balance loads and generation with or without energy storage and is capable of
islanding whether connected or not connected to a traditional utility power
grid.”
A very small microgrid is usually referred to as a nanogrid.
Nanogrids more resemble a single distributed energy source. They are typically
less than 100 kW with battery backup. A version larger than a microgrid is
typically called a virtual power plant (VPP). The boundaries can be blurred as
VPPs can incorporate microgrids and nanogrids as DERs. Two-way power flow is
important for any DERs and needs to be managed with software and smart grid
technology in order to remotely, automatically, and in real-time dispatch DERs
which can be linked to wholesale power markets. This can provide value to both
the utility and to the DER and microgrid operators.
While microgrids are being touted as the next big thing
among renewable energy enthusiasts, distributed generation advocates, and
anti-fossil fuel activists, it should be pointed out that the applicability of
microgrids is currently limited to certain situations. Eventually, as smart
grid technologies are more widely implemented there will be more opportunity for
distributed energy applications. So far as it is happening on a small-scale there
continues to be some disruption of utility grid management processes and
adaptation requirements. By one estimate the current U.S. microgrid market
makes up a mere 2 MW of energy production which is quite a small blip. However,
it is projected to rise fairly rapidly as the practicality of microgrids is
applied to applicable situations. Peter Fox-Penner, in his book, Smart Power, states:
“Many decades from now, much more power will be made locally,
within smaller-scale versions of our current grid known as microgrids.
Microgrids, which will range widely in size, will have a variety of local and
regional power sources as well as power storage options and will also often
draw on larger, relatively distant sources.”
“We will routinely
control and measure the cost of most of the energy-consuming devices we own. In
buildings that are grid- or micro-grid connected, all significant devices will
communicate seamlessly with the software that runs the resident grid. Parts of
what is now the single central grid will become parts of microgrids, and the
distinction between the Big Grid and regional and local networks of microgrids
will be a matter of degree, not black and white.
Off Grid Backup Power
Off grid backup power is one of the most useful applications
for microgrids. Facilities like hospitals where access to energy is a
life-and-death matter require backup energy sources when the grid goes down.
Other facilities like schools and certain industries can also benefit from
microgrid backup power. Industries requiring large-scale refrigeration of
perishable food productsd are particularly susceptible to power disruption. The
microgrids can also, of course, be used for primary power and also be tied to
the grid when the grid is running to take advantage of using the grid for
storage and extending battery life. In places where power outages are common or
tend to be long-lived due to weather, microgrids can be advantageous. Of
course, if snow is the weather issue it should be noted that solar power can be
quite poor in the winter season and snow removal from solar panels would be a
requirement. Backup microgrids can also utilize small natural gas turbines
where gas supplies are available or as is more common digital generators that
run on diesel, gasoline, or propane. These can help charge any battery banks if
battery backup is integrated.
Closer-to-Usage Applications of Decentralized Power and Combined
Heat and Power (CHP)
Decentralized power has the ability to be used closer to
where it is produced, reducing power losses from transmission, which can make
it more economic to buy once built. Without the need to be delivered by large
overhead power lines it can also be more resistant to storm damage. Local power
can be more reliable in terms of stable voltages, frequencies, and loads.
Traditional centralized power generation was built closer to sources of fossil
energy as well as closer to sources of water for cooling.
Microgrids may also incorporate combined heat and power
(CHP) which may give them an efficiency between 66 and 80% rather than below
50% with traditional centralized power. Basically, in any process that produces
enough waste heat, that heat can be converted into power by reciprocating
engines, gas turbines, steam boilers and turbines, microturbines, fuelcells,
and more. Microgrids can incorporate other local sources of power as well
including biogas from landfills and anaerobic digestors, waste-to-energy
facilities and other biomass plants. The excess stored heat may allow for
significant off grid functioning as well.
Community Solar
While community energy projects may involve multiple
generation sources including wind, micro-hydro, and fossil fuel backup, it is
solar that has and will continue to be the main source by far. Energy storage
may be added in the form of batteries or even fuel cells where applicable. Community
solar is another niche market for microgrids and distributed generation. People
like solar power because it is comparably environmentally benign. The first
community solar project was brought online in 2006 in the state of Washington
by a municipal utility. It also offers local groups a chance to maximize their
use of local solar energy in models where small-scale smart grid and energy
trading technologies are set-up as in the “blockchain” method described in the
reference. This is mostly limited and is really a “feel-good” sort of thing for
those who want to be rid of fossil fuel usage. In order to work in the model
noted for Brooklyn, New York it still requires the utility grid to be used for
temporary storage unless significant battery storage is installed. It is an
interesting model for solar-only distributed generation on an experimental
internet-based local distributed energy market with prices fluctuating
according to demand, also called dynamic pricing and time-of-use pricing.
Other
community solar models such as solar gardens and solar demonstration
installations for schools offer similar economics to residential rooftop solar and
vary according to area. Community solar is good for people who want to invest
in solar with little upfront investment capital and those who do not have ideal
roof space or roof orientation and whose neighbors in the project have some of
it to spare. Roof suitability is definitely an issue since by one estimate as
much as ¾ of U.S. roofs were deemed unsuitable for solar panels. Project
economics can vary quite a bit. Utilities or third parties (like Solar City)
could own and lease the systems and customers could pay monthly through higher
utility bills where the generation offsets the cost and it is simplified and
integrated into the single bill. Financed individual residential solar systems
do get quite low interest rates but any financing lowers the economics from a
full purchase – and the economics are not that great even with full purchase.
Community solar participants usually subscribe on a cost per watt basis which
has been dropping over the years. Subscribers are also eligible for the 30%
federal tax credit for solar installation.
Electric co-ops and municipal utilities represent the major
market share of community solar. 350 KW is a typical size of the electric co-op
projects but some projects up to about 750 KW are planned. Even investor-owned
utilities (IOUs) are becoming interested in community solar. They prefer larger
systems and those that can provide some current or future demand response and
grid balancing capabilities. They also have more regulatory hurdles than co-ops
and municipal utilities. How to value the systems on the utility customers’
bills is an issue of current interest. Utilities can essentially put community
solar projects where they want them so as to optimize their own economics while
also satisfying customer demand for solar which gives them both first mover
advantage and tends to keep solar disruption where they would prefer it. They
can utilize community solar to defer or avoid transmission and/or distribution
upgrades as well as peaker plants.
In 2010 there were only two U.S. shared solar projects but
now there are 111 projects administered by 77 utilities, mostly co-ops, in 26
states with a combined capacity of 106 MW. Community solar is expected to grow
59% annually through 2020 reaching an installed capacity of 534 MW. While that
may sound like a lot it means the ability to meet the energy needs of about
10,000 households now and about 50,000 households in 2020 so community solar
will remain a very minor part of the total electricity picture. Community solar
is typically oversubscribed so that those wanting to exit the deal or those
that default can be replaced by those on a waiting list. This can create some
customer management issues and costs. The advantage is that those who subscribe
to community solar rather than their own rooftop solar can control how much
they invest and for how long. Due to the rooftop suitability and financial
commitment requirements of rooftop solar it is very unlikely that rooftop solar
and community solar will ever be in competition. Clean Energy Collective (CEC)
has developed a software platform that integrates meter tracking with utility
infrastructure and customer billing. Virtual net metering, where multiple
customers receive apportioned credit for the system’s excess energy generation,
is one of the major features of community solar in states that allow it.
Currently, only a handful of states have shared solar policy mandates with a
few more in either pilot stage or proposed. Several states are involved in
negotiations between regulators, IOUs, and solar developers regarding rules for
sizing and locations of projects. Not surprisingly, low income areas have been
slow to get into community solar, obviously due to cost. Utilities need to be
careful to avoid shifting costs of integrating community solar to non-participating
customers which would be unfair. Co-ops can also get low-interest loans and
other financing help through federal programs. In order to get the tax credit
the co-ops may lease the system from the developer before buying it. IOUs have
tended to develop larger community solar projects, siting and sizing them to
best suit the needs of the IOU. This is a trend that is likely to continue.
Solar Co-Ops
Another community solar model is that of the solar co-op.
This is typically done by area or even county. Solar provider and installation
companies may also initiate and support projects since they will benefit as the
developer. Other organizations may also help to organize and even specialize in
development of group solar projects. Sign-ups for county-wide solar co-ops in
Ohio have had good turnout which suggests many people want to go solar in the
community solar format. Going solar as a group can offer discounted prices from
installers as this aggregation can allow them to eliminate some duplicate costs
for things like planning, permitting, and scheduling. These are also typically
much bigger projects for the providers than individual residential projects.
Utility Participation
Many microgrid projects are likely an annoyance to utilities
but there are some advantages. As in the community blockchain model mentioned
above they can test out how solar-only distributed energy will work on the
local level in various places and times. Such projects added up can help
utilities meet their renewable energy requirements for state RPS standards. It
can also perhaps give them more options for offering their customers chances to
buy renewable energy in the form of state renewable energy credits which also
helps them meet their RPS requirements. Eventually, utilities may be able to
benefit from these distributed energy sources, especially if they are rich in
battery storage so they could be utilized with software as backup power banks
reducing the need for peaker plants, so they contribute to “costs avoided.”
Distributed Energy Resources
Distributed energy resources, or DERs, also called distributed generation (DG), refer to energy
production sources that are not derived from large centralized power plants,
centralized wind farms, or centralized solar farms. Residential rooftop solar
is a major source as are small combined heat and power (CHP) plants, as well as
other small sources like small digital generators running on gasoline, diesel, propane,
or natural gas. Battery storage can also be considered a distributed energy
resource when added to small systems. The capability of running off-grid due to
battery back-up, the connecting of different generation resources as a unit,
and grid connection as a unit such as group net-metering – make a distributed
energy source a microgrid. One source estimated that there are a mere 2 MW of
microgrid capacity in the U.S. That is likely to grow drastically in the near
future and likely already is growing. New energy generation bundling and
sharing ideas are popping up all over.
According to Navigant Research cost effective DERs could
replace a staggering 320 GW of centralized generation from 2014-2023. They see
the current solar-plus-storage going from the current 2MW(?) to about 1800 MW
by 2025. These is a very bold prediction. The whole notion is predicated on
‘software managed energy storage.’ In my previous post about energy storage I
note multiple times about the problem of cost. Navigant expects 30-40% of
residential solar (basically nanogrids) to be aggregated into VPPs by 2025 as
smart grid technology is more widely implemented. Thus aggregated residential
solar, typically with some battery backup, and other DERs become VPPs. This could create huge opportunities for
ancillary services through DER management. Time-of-use bill management creates
value for the utility customers that have residential solar as well as other
DER owners. Smart grid technologies also include smart home IOT technologies
such as smart plug-load controllers, smart thermostats, and programmable water
heaters. In such systems where battery backup becomes widespread, each house
can island as a nanogrid, the whole block can island as a microgrid, and in
providing demand response the whole linked system can be considered a VPP.
Utilities may even set up such banked or aggregated nanogrids into VPPs,
charging upfront payments but benefiting from the DER demand response services.
Thus the utility manages the individual solar-plus-storage residential solar
nanogrids. Still, these projects are not economically feasible in today’s
pricing, either for the customer or the utility. The cost of solar and
particularly the cost of storage will have to come down further. The technology
is proven and works but by some estimates the battery storage costs would have
to be about 20% of what they are now to be truly economic. It seems that will
keep these “technology demonstrations” as just that and not as a massive
replacement of centralized generation any time soon as Navigant suggests.
A New “Business Model” for Residential Solar: The Scalable
‘Transverters Plus Smart Internal Demand Response’ Model
This is a rather fascinating model where potentially up to
50 homes or more could be tied together and utilized by the grid for demand
response and/or utilize internal demand response through plug computers and
smart demand response modules analyzing and adjusting power usage on short time
scales so that demand response could be maximized, individual electrical
systems could be downsized (from avg. 100 amp to 50 amp), and solar use could
be maximized. Battery backup is used in these systems mostly for short time
interval demand response and frequency and voltage balancing so that battery
life is extended. These systems could be grid tied in large enough blocks to
provide some grid-scale demand response which could significantly increase
their value. Alternatively, they could be backed up with digital generators
running on gasoline, diesel, propane, or natural gas to help with base load
when needed. This could better provide optimal sizing of generators rather than
oversizing them since these digital generators are capable of revving up and
idling down in response to power surges which saves on their fuel usage and
thus emissions. Scaling up the systems from home size to nanogrid to microgrid
should be easy and this scalable system may become an important microgrid type.
The biggest obstacles to widespread adoption of such systems is of course cost,
typically initial cost. Battery life and replacement costs would also be an
issue as would potential system maintenance issues. Large power using appliances
operation would be sequenced to prevent surges as in any IOT-style smart-home
technology. Remote system operation, including remote generator startup is also
employed. For the homeowner, these systems seem to be about 50-60% the value of
a comparable grid-tied system with the advantages that they can run off grid
and remove problems with grid integration of solar. Thus they could help the
utilities by diverting distributed solar away from the need to be integrated
and in the big system cases they could aid utilities by providing demand
response ancillary services. Several pilot projects are underway now to test
these systems. It is hard to see, however, how widespread adoption of them
could take place without the initial costs coming down. Both this model and the
similar blockchain model seem to be applicable for urban environments where
homes are close together, where optimal rooftop access can be shared, and where
net-metering can be aggregated. Heart Transverter, the company leading this
model touts these systems with the digital generator back up as ideal energy
systems to run cell phone towers. It may be interesting to see how many are
adopted in future by cell towers.
Solar-Plus-Storage Municipal-Scale Microgrids
Just recently it was announced that the first municipal
solar-plus-storage project in the U.S. will be built in the city of Minster in
Western Ohio. The city hosts a few large industrial plants which makes its
power needs large and the need for uninterrupted service vital. The batteries are
set to provide black start capabilities and to be accepted to bid as a
generator for the PJM interconnection frequency regulation market, in addition
to providing the utility with peak shaving, power quality stabilization, and
voltage regulation. These abilities allow the project to “stack value streams.”
In order to perform all these the functions the batteries had to be sized
large. In fact, optimizing battery size needs for any system that includes
multiple applications such as back-up energy, internal demand response, and
grid balancing, is important for optimizing costs. Reliability needs need to be
accurately assessed. The Minster project is financed by a backer with
investors. Municipal utilities are known for their ability to get projects done
quickly. This one is slated to take 18 months which is quick for a
utility-scale project. Of course the economics are dependent on the 30% federal
tax credit (ITC) as well as state renewable energy credits (SRECs) which
typically add another 5-10% of subsidization. The project is dependent on a
power controller in the form of embedded software.
The microgrid in Minster is planned to come after the
project is built in order to prevent blackouts at the industries which could
cause significant financial damage. It is estimated that $26 billion is lost
due to sustained outages and $52 billion due to momentary outages every year.
The municipal-scale microgrid could instantly “island” if power from the
utility (Dayton Light and Power) is disrupted. The microgrid could also
incorporate wind power and other distributed generation. Like the
solar-plus-storage project it will be financed by a public-private partnership.
Since “munis” and co-ops do not have to answer to shareholders or depend on
costly and time-consuming approval of large transmission projects and for a few
other reasons as well – they are more suitable for developing microgrids.
Traditionally, as noted, they have become known as well for implementing energy
projects quickly.
An important issue with solar-plus-storage is battery life.
While the life of a solar system may be 25-30 years (with about 1% panel efficiency
loss per year avg.) the life of lithium ion batteries is in the range of 5-10
years. This means at least two battery replacements during the life of the
solar system which obviously would add a significant amount to costs. I assume
the replacement costs would also be subsidized by the 30% federal credit and
possibly other incentives as well. Even so, if such replacement costs are not
accounted for in economic analyses then they are basically not accurate. The
replacement costs would also add to the total subsidization per KWh,
presumably. There is also some power usage, or loss, in charging as well as
discharging battery systems (10-20%? – I still have yet to find good data) which
also affects the economics significantly. For a municipal energy system that
requires long-term economics just over break-even, this may not be a big problem,
but it seems to me it constrains any large takeoff of solar-plus-storage which
would contradict the Navigant Research predictions.
The Energy Democracy Movement and Issues Between Utilities and Community-Based DERs
One offshoot of the microgrid and community energy trend is
the energy democracy movement. This movement can be quite political and may
share the view of the growing fringe Democracy Over Corporations movement and
is basically a foray into anti-corporatism. Some liberal universities are
aligning with such trends. It is one way that anti-corporatists are
diversifying their community focused activities in order to advance an
ideology. In a less ideological way perhaps is the energy democracy advocated
by John Farrell of the Institute for Local Self Reliance (ILSR). They advocate
for more energy generation owned by individuals, energy co-ops, municipalities,
and the community. While it is true that the distribution end and two-way flow
from and to it will be a growing feature
of the whole grid system in the future there are many utilities (‘munis’, IOUs,
and co-ops) planning for it while also building centralized plants, mostly
natural gas ones to replace coal. The ILSR thinks that not enough investment is
going to DER and too much for old-style distribution upgrades. They are
advocating that the utilities hedge their bets on undeveloped and costly
technologies like DERs and EVs. There is much debate about how the utilities
should integrate these competitors by buying their energy and giving them free
or cheap transportation services. Relying on old business models where
utilities seek to profit from energy sales rather than energy services is
slowly fading, too slowly for some. This revenue decoupling has succeeded
modestly (or not according to some) in California and will likely occur
everywhere eventually as the values of energy services are commodified in ways
that are agreed by utilities, utility commissions, regulators, federal and
state governments, and power customers. Utilities traditionally set rates for a
certain degree of guaranteed profit. Since they will have to increasingly
compete with DERs they tend to see that as a threat even though there are some
potential benefits of utility-DER collaboration.
The German “Energy Transition” has brought power generation
back to people and communities with mixed results. They are currently at the
limits of “grid integration,” so it should be interesting to see what happens
going forward. The Community Rights Movement is another similar grassroots
effort toward local control of resources, industry, and regulation. While all
of these movements are certainly forces to be reckoned with, they by and large
tend to be confrontational here in the U.S. rather than collaborative as well
as biased and often uncooperative, and uncompromising. They tend to despise
natural gas due to the backlash against fracking. This is unfortunate since
creative integration of renewables and small-scale natural gas can solve many
local energy issues adequately. Perhaps recent happenings with the firing of aggressive
solar advocate Bryan Miller from both Sunrun and the Alliance for Solar Choice
(TASC) amidst the net-metering wars between utilities and solar advocates in
Arizona and Nevada indicate that the solar industry in general is moving toward
a collaborative rather than a confrontational approach, one which may have
perhaps prevented the recent Nevada move to eliminate net metering. Another
indication is Solar City’s hiring of former FERC chairman Jon Wellinghoff as
chief policy officer.
There is already backlash against “corporate solar,” or “Big
Solar,” larger companies getting into installation and gobbling up smaller
companies. These bigger companies like Solar City, Vivint, Sunrun, and
SunEdison can take advantage of economies of scale, process and product
standardization, volume purchasing, on-line planning and sales, and market
saturation. While some may see this as less ‘personalized’ service, there are
significant cost advantages to the customers and with solar’s tough economics
adding value for the customer is important. However, it also means less high-paying
career opportunities in solar sales and installation. For this reason some are
advocating for unions in the solar industry. The recent offer from Tesla to buy
Solar City may be seen as a consolidation of the natural complementary
industries of solar and storage or it may be seen as Big Solar-Plus-Storage.
While DER in the form of residential solar may seem to give more power to the
people as independent energy producers they are also benefited by subsidization
and force their competitors, the utilities, to buy and transmit their excess
power, which may help and/or hinder the utilities. Unless and until
solar-plus-storage becomes truly economic, which may take several decades
rather than one, the DER producers will be dependent on the macrogrid. They
also depend on the macrogrid to become more economic as providing demand
response services to the macrogrid will make their installations pay out
faster. Consolidation in the solar and battery storage industries (Big Solar
and Big Storage) will also help their installations pay out faster. Thus, the
‘power from the people’ advocates depend now and will depend for some time to
come on both government handouts and corporate handouts. The most valuable
corporate handouts come from both Big Utility and Big Solar/Storage and yet it
is no secret that many in that camp would love to ‘bite the corporate hands
that feed them,’ only if it were economically possible. Utility business models
are changing and will continue to change to integrate DERs while also
maximizing value for their shareholders and their customers. The
confrontational approach of the more radical energy democracy advocates is not
the most sensible approach since they are dependent on those they choose to see
more as adversaries than collaborators. Hopefully, the future of energy
democracy advocacy will be more reasonable and less confrontational. That would
be in everyone’s best interest. It is also true that utilities need to adapt to
DERs, not as a threat but as a collaborative opportunity. Even so, they also
need to wait until the solar and storage technologies become cheaper and the
smart grid technologies become more functional and widespread for any
widespread adoption of pro-DER business models.
The current state-level debates about net-metering show that
the utilities do not want to be forced to lose value and even some efficiency
gains by integrating DERs. Even so, as quasi-monopolies with guaranteed profit
structures one might think they could be more adaptable. Big utilities are not,
in that sense, free market corporations, but government-assisted entities which
should thus have at least a little more accountability to the public, both in
power rates and integration of DERs. It is complex but models will come in
time, especially if DER costs go down. Peter Fox-Penner stresses the need for
reforms in both energy pricing (rate-structure) and oversight. He gives two
versions of new business models for utilities: the Smart Integrator model for
states which have adopted deregulation where energy distribution companies
transition from energy providers to energy service providers; and the Energy
Services Utility for states without deregulation and with predominant IOUs
which develop subsidiaries that focus on the value of energy services.
Traditional energy companies in Germany, where renewables and DER penetration
is very high, have suffered significant revenue losses and plant closures. Such
revenue losses, says Fox-Penner, may force traditional energy companies to
become Smart Integrators and Energy Service Utilities. The companies argue that
the costs associated with integrating DERs must be born equally by those who do
not own DERs, making power costs rise for all. It is a rather important paradox
for the traditional power industry. Fox-Penner asks:
“What kind of industry would invest one or two trillion
dollars simply to sell less and less of its product as its customers took
control, and made more of their own energy, and other companies grabbed a
larger and larger share of the value chain”
In addition, due to these needed grid investments, upgrades,
efficiency investments, and increased operating costs, the price per KWh for
customers will rise even as electricity consumption remains steady or even
drops. There is value to DER but in order to harvest it the utilities need to
retool their models. It seems that it will remain a difficult and controversial
task. Fox-Penner also notes four fundamental objectives of modern power
sectors: 1) adequacy, which is simply sufficient energy supply to avoid
shortages; 2) reliability, which means uninterrupted supply – this is extremely
important for certain industries – base-load power sources and energy storage
are required to mitigate the reliability issues of renewables; 3) affordable power
availability for all – this is very important now for developing countries; and
4) decarbonization – this favors renewables, increases their public value, and
justifies the increased costs of developing and integrating them.
References:
Driven by Power Outages and Savings, Towns Look to Microgrid – by
George M. Walsh, Associated Press, posted Feb. 7, 2016
Microgrid Presentation at Ohio University, presentation and discussion,
Jan. 28, 2016
Community Solar Poised for Growth as Utilities Gain Confidence,
Familiarity – by Herman K. Trabish, in Utility Dive, April 7, 2016
Power From the People: How to Organize, Finance, and Launch Local
Energy Projects – by Greg Pahl (Post-Carbon Institute/Chelsea Green Publishing,
2012)
Beyond Utility 2.0 to Energy Democracy: Why a Technological
Transformation in the Electricity Business Should Unlock an Economic
Transformation that Grants Power to the People – by John Farrell, ILSR
Democratic Energy Initiative, December 2014
The World’s First Consumer Blockchain Energy Transaction Begins “Power
to the People” Revolution in New York – by PennEnergy Editorial Staff, April
11, 2016
Microgrid – entry at Wikipedia.com
Addressing the Challenge of Distributed Energy Resource Growth and
Keeping the Lights On: How the Electric Utility Industry is Coping with the
Rise of Distributed Energy Resources – white paper form westmonroepartners.com
Smart Power: Climate Change, the Smart Grid, and the Future of Electric
Utilities, Anniversary Edition – by Peter Fox-Penner (Island Press, 2014)
Fuel Cells Are a Good Partner for Microgrids, But Costs Limit
Deployment – by Peter Maloney, posted at Utility Dive, May 10, 2016
Implementing Microgrids: Controlling Campus, Community Power Generation
– by Paul Barter, PE, ESD; and Edward T. Borer, PE, Princeton University, in
Consulting, Specifying Engineer, June 8, 2015
Optimization of a Battery Energy Storage System Using particle Swarm
Optimization for Stand-Alone Microgrids (Abstract) – by T. Kerdphol, K. Fuji,
Y. Mitani, M. Watanabe, and Y. Quddaih, in International Journal of Electrical
Power & Energy Systems, Vol 81, pgs 32-39, October 2016
Heart Transverter – Residential Solar with Transverters – by Heart
Akerson, CEO Heart Transverter, www.transverter.com
Unlocking the Value of Community Solar: Utilities Find Opportunity in
the Inevitable Growth of Distributed Energy Resources – by Deloitte Center for
Energy Solutions, Marlene Motyka, Andrew Slaughter, and Julia Berg, 2016
Add Value, Reduce Cost, Eliminate Risk: OCCUPY SOLAR OHIO – Commentary
– by David Dwyer, in Green Energy Ohio News Magazine, Vol 9, Issue 1, Spring,
2016
The Lorain County Solar Co-Op Selects an Installer – by Luke Sulfridge,
in Green Energy Ohio News Magazine, Vol 9, Issue 1, Spring, 2016
Fanning the Flames of Solar Enthusiasm: The Delaware County Solar
Co-Operative – by Dave Carpenter, in Green Energy Ohio News Magazine, Vol 9,
Issue 1, Spring, 2016
Inside the First Municipal Solar-Plus-Storage Project in the U.S. – by
Herman K. Trabish, in Utility Dive, July 5, 2016
How Storage Can Help Solve the Distributed Energy ‘Death Spiral’ – by
Herman K. Trabish, in Utility Dive, June 21, 2016
Bryan Miller Ousted from Sunrun and TASC: What Does It Mean for State
Solar Advocacy – by Stephen Lacy, in Green Tech Media, July 7, 2016
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