Distributed Generation, Microgrids and Non-Transmission Alternatives

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Erik Wilkinson of ISO New England Steve Hinchman of GridSolar Dan Kelley of Woodward Curran and John Carroll of Iberdrola photo by Kay MannFollowing up on its March 2014 forum on the needs of and issues with the regional electricity grid, or "macrogrid",  the Environmental and Energy Technology Council of Maine (E2Tech) presented a discussion of distributed generation (DG) and "microgrids" in Maine on April 17, 2014.

The forum aimed to answer the following questions: What resources are available to fuel these systems? What transmission and delivery or T&D rate structure changes will support grid investment and reflect long-term benefits of locating DG in areas with reliability concerns?

Benefits may include enhanced cyber-security, increased renewable sources of electricity like wind and solar power, and even integration of electric vehicles onto the grid. This forum offered an opportunity for collaboration among ISO-NE, state policymakers and regulators, energy companies, and others on operational, planning, and market implications of these non-transmission alternatives. Green Energy Maine was there and brings you this report.

Erik Wilkinson of ISO New England photo by Kay MannFORECASTING DISTRIBUTED GENERATION

The panel was moderated by Bill Ferdinand of Eaton Peabody. The first panelist introduced was Erik Wilkinson, External Affairs Director for ISO New England.

ISO New England is a nonprofit that operates the entire New England grid from a power station in Massachusetts. They also administer the wholesale energy markets in NE. They are resource neutral and do not own any generation. Their primary mission is reliability and they are regulated by the FERC. They are also responsible for system planning.

The definition of distributed generation is any generator of 5 MW or less in nameplate capacity which is connected to and can supply the grid, following state-jurisdictional interconnection standards. Distributed Generation is growing. The ISO is planning for this and is accounting for it in its future planning efforts.

The ISO sees DG in three ways:

1. These resources can participate in the forward capacity market and contribute to the installed capacity requirement and are well-understood.
2. "Settlement Only" resources can participate in energy markets, are counted as load assets and are also well-understood.
3. "Other" DG reduces load, is embedded in historic loads used for forecasting and are less well understood than the first two.

ISO has created a Distributed Generation Forecast Working Group (DGFWG) in order to have a sounding board with stakeholders, giving them information to help them plan 10 years out and further. This will keep evolving and new stakeholders are welcome to participate.

Solar is the largest component of DG at this time in New England, so this forecasting group has been focused on solar. Data is collected from states about their pv goals and production queues. Discount factors must be applied to nameplate capacity figures due to the intermittency of solar production.

Massachusetts leads New England in installed solar capacity with 340 MW; Maine trails with 8 MW. Over 2500 MW of nameplate pv is forecasted for all of New England within 10 years. This forecast will be incorporated in all of ISO-NE's overall planning forecasts for the entire grid.

One challenge with solar is interconnection standards. The regional interconnection standards for DG are generally consistent with IEEE Standard 1547TM, which is a “don’t ride through” requirement. This means they are shut down during small power interruption events. Further standardization across state lines is needed, to provide state-jurisdictional interconnection.

Steve Hinchman of GridSolar photo by Kay MannNON-TRANSMISSION ALTERNATIVES

The second speaker on the panel was Steve Hinchman, Counsul for GridSolar, LLC. His talk was entitled, "Using a smart(er) grid to lower costs, energy use, and pollution".

In 2009, GridSolar conducted a study that concluded that non-transmission alternatives (NTA's) such as distributed solar generation and smart grid technology could provide an alternative to the $1.5 billion Maine Power Reliability Project or MPRP. Regulators were not convinced, so asked GridSolar to conduct a pilot study to demonstrate how this could be done on a small scale first.

Thus were born the MidCoast & Portland smart grid demonstration projects and the Boothbay NTA pilot project. These projects all attempted to reward optimizing smarter use of the grid to reduce excess loads.

Reliability on the CMP grid is a peak load problem. Distributed solar is a good solution to solve this load shortage because it occurs at only a few hours per year and these times happen to coincide with times of high solar production. So it is possible for peak load to be met through solar DG. However, back-up generation systems (BUGS) and smart grid technology (SGT) are needed for a perfect load match.

When CMP analyzed the 10-year transmission needs from the Boothbay peninsula to Newcastle, they concluded that they would have to rebuild the 34.5 kV line at a cost of $18 million or $3 million per year over 6 years. The GridSolar alternative was simply to add 2 MW of NTA's by 2020. The hybrid solution includes substation upgrades for voltage shock and 2 MW of NTAs for Thermal Violations (Sag).

The Boothbay pilot design is for 3 years with an option to 10 years. The NTAs being used are efficiency, renewable DG (125 kw solar), non-renewable DG (preference net zero CO2), backup generators (BUGS), demand response and battery storage. The goal is to gain up to 250 kW from each of these, and they are all scalable.

Grid Solar has put out 2 RFP's for the NTA's and has received bids that are all lower than new transmission costs. The all-in price of the NTA system has been less than the transmission system and is projected to drop to less than half of transmission system costs over the period 2013-2023.

The GridSolar operations center in Portland will have a dispatch system (SCADA) and a command interface that allows it to respond at times of greater demands from CMP. This includes a direct/cellular link to active NTAs and data loggers at passive NTAs and is in the testing phase now.

One system for demand response makes ice at night in a box next to the chiller on a large building and routes cooling pipes through the block of ice in the daytime.

One problem with the smart meters that have been installed on all CMP customers is that they lack a certain chip that would enable customers to pay different rates at different times of day. This eliminates demand response as a large-scale solution.

GridSolar concludes that the investment in NTA's can be matched to power needs at a much lower cost than building new transmission capacity. This is a step toward a smarter electric grid in Maine and New England.


The third speaker of the morning was Dan Kelley, Vice President of Power Engineering for Woodard & Curran.

Distributed Generation (DG) is generation located at or near the load site. It is not a single technology but a group of technologies. It can reduce energy costs or dependence while improving reliability and reducing disruptions.

DG in the form of combined heat & power (CHP), co-generation and other technologies have been in place for over 100 years.

The benefits of DG include:
Positive effects on local economies;
Enhancing energy security;
Advancing climate change goals;
Business competitiveness and
Improved reliability and efficiency.

More than 2/3 of electric power is lost over great distances of transmission, so using power closer to the generation site is much more efficient. By comparison, CHP systems achieve 2 outputs with one fuel input.

DG options are sized to meet users' thermal and power base loads. Systems can be installed behind the meter or can use net metering or PPA's.

Kelley gave a list of DG technologies:
Combustion turbines;
Reciprocating engines;
Biomass boiler/backpressure steam turbines;
Fuel cells;
Renewable energy such as solar or micro-wind.

The best candidates for DG sites include:
Education institutions;
Hospitals and nursing homes;
Real estate communities;
Hotels and conference centers;
Food services;
Manufacturing or process industries;
Municipal or public buildings;
Correctional facilities;
Museums and
Data Centers.

This market is largely untapped at this time. CA and NY are leading the way with more installed DG than other states; PA and TX are close behind.

Good target applications are those that have:
High electrical and thermal loads;
Thermal energy loads for hot or chilled water;
High operating hours or load of over 4,000 hours per year;
Consistent load desired;
Doubling as emergency power or
Mission critical load sources.

Microgrids are DG systems with the added benefit of different drivers such as recent natural disasters or weather-related outages. They are not popular in northern New England. They do provide an insurance policy against service disruption, but require a great deal of interconnection and coordination with the local utility.

John Carroll of Iberdrola photo by Kay MannTHE UTILITY PERSPECTIVE

The last to speak was John Carroll of Iberdrola, USA (parent company of CMP). Carroll began by saying that CMP sees the benefit to consumers of all these new technologies. The grid is the system that enables these technologies to be developed: the social and economic benefits are a product of the interconnection with the system.

Utilities gauge costs and benefits on a system basis; the goals of safe and adequate service must be balanced with providing just and reasonable rates.

Microgrids are complex systems that are capable of isolating from the grid and operating as "islands" while maintaining a stable supply demand balance and quality power.

Drivers for the development of microgrids are increased reliability in emergency conditions, government incentives and policies, low natural gas prices and advances in generation technologies.

Trends CMP is seeing include:
Limited installations in universities and military;
Niche opportunity to create self-sustaining islands for disasters and
Taking existing options such as back-up generation or dual feed agreements to the next level of reliability.

CMP sees all these new technologies changing the future of its industry. DG systems are relatively unknown as to reliability and technology.

Where you have customers who are very sensitive to reliability and quality of power, for example a hospital, you have to be careful about power supplies to the particular circuit from which they get power. The impacts of some DG systems on the circuits they connect to are positive and some are negative.

DG System benefits to a utility are comprised of avoided energy generation, deferred capacity, deferred T&D, avoided line losses and emissions reduction.

Utility considerations with microgrids and DER
1. Standardize interconnection rules and protocols;
2. Assessment and deployment of advanced distribution technologies;
3. Integrate DER with grid planning for T&D and
4. Align policy and regulations.


Q: Is it possible to incentivize different time of use rates for instantaneous use customers?

A: Smart Grid (SGS) meters do not have the chip in them that enables time of use rate differential.
There are two ways to store energy for later use: one device is a thermal electric storage space heater and the other is an electric vehicle.
GridSolar is looking for technology to pay small generators to feed power into the grid.
The suite of NTA technologies will grow rapidly.

Q: If 1/3 of the circuits are not good candidates for DG, how can this be improved and at what cost of investments, compared to those required to meet demand increases by traditional means?
John Carroll: There are 470 circuits in Maine and these are dynamic as demand shifts around. To give incentives for this technology, you should recognize that any DG system may raise or lower the utility's T&D costs, depending on many variables.

The slides from the four speaker presentations are here. All photos by Kay Mann.

See what is next from E2Tech here.