Markham, Ontario: On April 2,GE announced their involvement with PowerStream in a joint microgrid demonstration project, located at PowerStream’s headquarters in Vaughan, Ontario. Originally launched by PowerStream in November 2013, the project is demonstrating how energy consumers and utilities are able to generate and distribute their own energy using renewable energy resources to address the growing demand for safe, sustainable and reliable energy resources.
For the project, GE provided its Grid IQ™ Microgrid Control System (MCS), as well as the engineering design services, to help PowerStream build its microgrid, which uses renewable energy resources (wind, solar), a natural-gas generator and energy storage devices (including GE’s Durathon Battery technology) to provide electricity for loads at its head office including lighting, air conditioning, refrigeration and electric vehicle charging. Using the MCS, PowerStream can determine when it is most economical to use the resources powering its microgrid or when they need to revert to using power from the provincial power grid.
“Microgrid technology is an innovative distributed power solution that will provide consumers with safe, sustainable and reliable energy choices for both generation and consumption,” said Brian Bentz, President and CEO of PowerStream. “We are pleased with our choice of GE as a partner in this microgrid project.”
PowerStream’s microgrid is essentially a pilot project at this point, explains Martin Rovers, PowerStream’s Director of Energy Services and Solution, designed to give the utility experience in running such a system using a variety generation and storage technologies (listed below). That experience will be needed so that PowerStream can deal with growing interest in such systems from customers.
“We’re having a lot of good discussions with customers who are interested in the same thing,” he said in a telephone interview, “but at the same time they want to work with their utility. Not everyone wants to figure it out on their own. That’s what the pilot project is about, it’s building experience to work with our customers. We’re technology agnostic, so we’re working with a number of technologies, in order to be able to advise an interested customer on what will work for them, and also how to connect to the grid.”
Those interested customers range from businesses down to individual homeowners – there’s nothing new about someone putting a few solar panels on the roof, but improvements in both generation and storage technologies, and the costs thereof, is renewing interest in the option.
The really interesting part lies in the potential to use one’s microgrid to offer the power system a demand response service. Using its microgrid, PowerStream can take its headquarters off the grid, partly or entirely – depending on what the sun and wind are providing, and using power stored in the batteries – any time. The next step involves adding the capacity to let the system operator know about the reduction in demand, so that one can get paid for it.
“The only thing we need to do now is add the ability to talk to the IESO so they can verify what we’re doing and pay us for it.” That part will come next, Rovers says. It will require an extra level of capability in the control system, although there isn’t a fixed schedule for it yet. “We are going to wait to add that capacity until we understand the market better.” And then it becomes a complete package of expertise that the utility can offer interested customers.
“Microgrids provide a benefit to the grid as a whole, in reducing the amount of generation, transmission and distribution infrastructure that has to be built. The IESO creating the demand response market is a way of rewarding that.”
PowerStream’s microgrid relies on power from:
• Solar panel: 17 kW, 81 SunPower 210W solar modules on dual axis trackers
• Lead acid battery: 23 kWh capacity
• Lithium battery: 12 kW power, 5 kWh capacity
• Na-Ni-Cl battery from GE, 6 kW & 12 kWh
• Solar carport: 5 kW, 20 panels at 250 w
• EV charger: 14.4 kW, 2 x 7.2 kW each
• Natural gas generator from Caterpillar, 35 kW, by Toromont
• Wind turbine, 1.8 kW from southwest WindPower
• Building load management (9 kW maximum).
PowerStream says the project marks the next phase in the company’s progress toward its goal of supporting smart grid development at the provincial level and raising awareness for the need to leverage innovative ‘smart’ technologies in Ontario’s electricity sector.
Modes of operation
The PowerStream Micro-Grid is designed to seamlessly connect or disconnect from the distribution system. When connected to the grid, the phase, voltage, frequency, and phase angles of the renewable energy generation sources, batteries and system loads are synchronized to the grid. Its four modes are as follows:
1. Supply to Grid
The microgrid is connected to the distribution system and supplies energy to the grid using renewable solar or wind power. Stored electricity from the Sodium Nickel Chloride, Lithium Ion Battery and Lead Acid Battery Systems can also be transferred to the grid. During the Supply to Grid operating mode, the natural gas generator will not be operated.
2. Supply from Grid
The microgrid is connected to the distribution system and is taking energy from the grid to serve its load. Electricity can also be stored in the Sodium Nickel Chloride, Lithium Ion Battery and Lead Acid Battery Systems for future consumption. During the Supply from Grid operating mode, the solar photovoltaic system and wind turbine system may also be powering the load and charging the batteries, but the natural gas generator will not be operated.
3. Island (Generator)
The microgrid is designed to operate in isolation from the distribution grid when in the Island (Generator) operating mode. During this mode, the natural gas generator will be the primary source of electricity with the renewable solar and wind generators providing supplementary power. Electricity stored in the Lead Acid, Sodium Nickel Chloride and Lithium Ion Battery Systems can also be used at this time.
4. Island (No Generator)
The microgrid is designed to operate in isolation from the distribution grid with the Island (No Generator) operating mode. During this mode renewable solar and wind generators will be primary source of power. Electricity stored in the Lead Acid, Sodium Nickel Chloride and Lithium Ion Battery Systems can also be used at this time. Since all generation sources are intermittent with this operating mode, low priority Micro Grid loads may be disconnected depending on the amount of generation available.
5. Black Start
The microgrid is designed to have black start capability that involves using backup systems to help launch the Micro Grid’s generation sources. During this mode, the Micro Grid is not connected to the distribution system and does not have electricity serving its load. The Micro Grid will use the backup systems to initiate the renewable generation sources and connect the battery systems to help restore power to system loads.
6. Unintentional Grid Outage (Generator)
The microgrid is designed to operate in the event of an outage on the distribution system and provide continuing seamless service to its loads. In this scenario, the Micro Grid will automatically disconnect from the grid and start drawing electricity from the natural gas generator, renewable energy sources and battery systems.
7. Unintentional Grid Outage
(No Generator)
The microgrid is designed to operate in the event of an outage on the distribution system and provide seamless service to its loads. In this scenario, the Micro Grid will automatically disconnect from the grid and start drawing electricity from renewable energy sources and battery systems. Since only intermittent generation sources are available, low priority Micro Grid loads may be disconnected depending on the amount of generation available.
8. Intentional Grid Outage
(Generator)
The microgrid is designed to operate in the event of a planned outage of the distribution system and provide continuing seamless service to its loads. Utilities periodically schedule planned outages to allow for maintenance and servicing. In this scenario, the Micro Grid will automatically disconnect from the grid and start drawing electricity from the natural gas generator, renewable energy sources and battery systems. The battery systems would be fully charged ahead of time to maximize the amount of power for loads during this kind of outage.
9. Intentional Grid Outage
(No Generator)
The microgrid is designed to operate in the event of an outage on the distribution system and provide seamless service to its loads. Utilities from time-to-time have planned outages to allow for maintenance and servicing. In this scenario, the Micro Grid will automatically disconnect from the grid and start drawing electricity from renewable energy sources and battery systems. This operating mode involves a planned outage and hence the battery systems can be fully charged ahead of time to maximize the amount of power for loads during the outage. However, since only intermittent generation sources are available, low priority Micro Grid loads may be disconnected depending on the amount of generation available.
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