Microgrids don't pose an immediate threat to diesel generators as the way most managers ensure their facilities have backup power, but Allan Schurr, the chief commercial officer at microgrid company Enchanted Rock, expects more operators to look at what he says is a cleaner, administratively easier approach that microgrids offer.
“Diesel generators are in short supply and sometimes it's two years before you can get a diesel generator delivered,” Schurr told Facilities Dive. “By having a microgrid … you can [have something] more reliable and cleaner” and have it up and running within a year.”
A microgrid is a self-contained electrical network that companies like Schurr’s install on their client’s property. Enchanted Rock builds its network using half-megawatt natural gas generators that it gangs together based on the amount of load the client wants to back up. For a hospital, it might be a network of 10 generators. For a grocery store, it might be two or three.
“Our standardization of equipment is part of our differentiator,” said Schurr, referring to his company’s use of a single-size generator. “That allows us to dial in exactly the amount of backup power that's needed for any facility size.”
Power from the microgrid is cleaner, Schurr says. In the case of Enchanted Rock, it’s cleaner because it’s generated from natural gas. But microgrids can also use solar, wind and other non-fossil-fuel burning sources.
The cleaner power might be important to organizations that make sustainability a priority but it can also help lower energy costs by enabling the microgrid to run power outside of emergency situations and sell it as a supplemental power source to the local utility grid. That revenue goes to the microgrid and helps offset what the property owner pays for its backup power.
“So, [our clients] can get the air permits to operate in nonemergency hours, and that's where the cash register comes in,” Schurr said. “If you can operate outside of emergencies, you can get paid by the grid to run during certain critical peak hours, and those payments offset the cost of the resiliency function.”
Avoiding test disruptions
Having the power run alongside the grid also solves one of the biggest headaches facilities managers deal with when they have a backup generator, Schurr said: the annual test.
In the typical case, the operator can start up the generator only after first shutting down the regular power, disrupting work for about 10 seconds at the start of the test and then again at the end, during which gaps there’s no power flowing to the facility.
“All the tenants in that building, whoever they might be, experience that first little outage, and then when you go back onto grid power, you take another outage before you connect to the grid again,” he said.
To avoid the disruption, some operators conduct the test without transferring the load to the generator. By doing that, they can get assurances the generator works but not whether it can carry the load that would be needed if there’s a power loss.
“They just start up the generator and it idles,” he said. “‘Started. Worked. We're good.’”
Some operators get around the disruption by testing the generator on a simulated load. “You bring in what's known as a load bank, which is literally like a giant toaster,” he said. “It creates a load for you to test,” but it’s expensive.
The other alternative is not to test at all. That’s not an option for hospitals and other regulated facilities that require annual testing to ensure continuous power to critical infrastructure. But for other facilities, the annual test rarely survives a budget cut.
“Those service contracts are one of the first things that get deferred,” he said. “Facility managers know this well. They never have the budget to do what they want to do, and so they're always looking for ways of stretching their O&M dollars, [which could yield] the kind of slippery slope that is a lack of reliability.”
One-year installation
Diesel generators are in short supply right now, so Schurr sees an opening for companies like his. Rather than wait two years to get a generator installed, operators can get backup power within a year. That’s about what it takes to get the network built out on the client’s property and tie the network into the local utility grid.
“One of the critical path items is getting the gas interconnect from the local gas utility,” he said. “So, we order the equipment for the electric switch gear, the gas interconnection and then we do permitting and construction. And usually within a year, we can be completed and operational.”
Separate from providing the property on which to build the grid, the client pays a set-up fee to do the construction work and install the network and then a monthly service fee – basically, a subscription – to have the company maintain and operate the microgrid.
“They get the full gamut of the maintenance and operation inside of that fee unless there's an outage, and then they pay fuel during that outage,” he said.
Enchanted Rock typically owns the microgrid and therefore owns any revenue it generates from selling surplus power to the local grid, which helps keep down the service fee to the client. In some cases, the client elects to own the microgrid, making it the seller of the surplus power.
Schurr touts this resiliency-as-a-service model as a way to make backup power generation economically feasible for organizations that might otherwise hesitate to invest in it.
“We have grocery stores that want to be there for their customers when there's an emergency,” he said. “They don't want to close down. They don't want to throw out all the food. They want to be open for business. So, we have customers in a lot of different industries that are trying to serve their customers better. And by so doing, they think that the business case is very strong.”