With 47 microgrids serving 58 communities, the Alaska Village Electric Cooperative (AVEC) is one of the most experienced microgrid operators in the nation. AVEC also has the unique claim of operating the largest service area of any retail electric cooperative in the world, including interior, western, and southeastern Alaska.
With a diverse portfolio of power generation equipment including assets from all major OEM’s, and only one of the communities served accessible by road, AVEC has been faced with the ongoing challenge of remotely managing and controlling their microgrid assets in extreme climates, with each OEM’s equipment presenting different challenges to operate.
Equipment from one OEM presents nagging issues with switchgear controls; equipment from another OEM suffers for lack of configuration flexibility. Regardless of the OEM, the most persistent issue faced by AVEC is that OEM control systems forced them to work with different support staff and external technical experts costing time and money.
Bill Stamm, Engineering Manager at AVEC, elaborates how “flying a technician into one of our communities to troubleshoot and repair a generation issue takes at least a day of travel, more if the weather is bad.”
In all, AVEC’s microgrid fleet includes 157 diesel reciprocating engines, incorporating assets from all major OEM’s running in continuous power conditions. Each site contains anywhere from 3-6 engines ranging from 100KW to over 2MW each; several locations also incorporate renewable energy from wind turbines. There are a lot of potential points of failure.
“With our diverse mix of equipment and the remote nature of our communities, anything we can do to standardize installations with solutions that are repeatable and adaptable helps to reduce operating costs,” says Stamm.
Getting it Right
In 2016, AVEC set out to solve their control issues by implementing 3rd party control systems in a pilot project, with the intention of deploying a fleet-wide solution over time. The first project was a new plant, which was partially funded by FEMA dollars to replace a flood-damaged plant in Teller, Alaska.
“The goal in specifying new engine controls was to find a unit with broad applicability, remote connectivity, in-the-can logic for synch-check, paralleling and load sharing and adaptable programming that was not going to bleed us for software licensing to maintain our fleet,” explains Stamm.
The pilot plant was built on an 18 by 57-foot base, encompassing three 236KW generator sets and six feeder breakers, and fully commissioned in Anchorage, before being transported by ocean barge, to the Teller location. The contract scope included four ComAp IS-NTC-BB, four IV-5, and one IV17T2, with programming, pre-deployment testing and on-site commissioning.
Stamm elaborates, “when we started our search, no one here had any experience with ComAp. They quickly made it to the short list with a long list of engine manufacturers and models with which they could communicate directly with the Engine Control Unit. We ordered samples from three control manufactures and did some bench testing; the manufacturing and finish of the ComAp components were sound, the programming was straightforward and well supported, and when we reached out to product users, people said given a choice, they would use ComAp again.”
The Teller Power Plant was commissioned in October 2017, and since then AVEC has continued to standardize with ComAp controls by retrofitting multi-engine and switchgear controls in existing power plants in Huslia and Eek and specifying ComAp for the new power plant under construction in Togiak.
The total upgrades for AVEC include switchgear updates from fused disconnects to electrically operated stored energy breakers, full system automation including power management, load and time of day unit dispatching, SCADA development, synchronizing, load demand swapping, run hour management, controller retrofits for the engine, tie and feeder management.
Plans include installation of ComAp gear for diesel engine and feeder control in St. Mary’s where AVEC is installing wind generation and extending the grid Mt. Village. The resulting microgrid will allow AVEC to share the benefits of renewable generation and automated controls with four communities including Pitkas Point and Andreafsky.