Hoboken Explores Smart-Grid Technology to Keep Lights On in Extreme Storms
The city would basically build a power grid of its own, but critics argue project may be too complex, too costly
For days after Hurricane Sandy, much of Hoboken was underwater. The hospital was shut for five days; the power was out in some parts of the city for nearly two weeks; and some residents had trouble getting basic necessities like food and water.
Hoboken Mayor Dawn Zimmer was out going door to door to survey the damage and tell people that the chef for singer Brad Paisley was out in Church Square Park, cooking food for local residents. When she reached Church Towers, a senior housing complex, she saw the lights were out everywhere, even in the hallways, the elevators weren’t working and the fire suppression systems was out of commission. Upon seeing Zimmer, an elderly woman hugged her and burst into tears.
“How could they leave us completely in the dark?” the woman said. She told Zimmer she was afraid to go down the stairs because she feared she would fall.
Zimmer said she could see into the woman’s apartment and it was filled with candles. She wondered what would have happened if there was a fire.
“That was my biggest concern, that the fire suppression system was not operational,” Zimmer said. Not only didn't the sprinklers go on, but also the fire alarm didn't ring. “There’s no way for people to even know there’s a fire,” she said.
She vowed that once the storm was over, she didn’t want the city to remain in the dark again. She reached out to the Department of Energy to learn what Hoboken could do to keep its lights on, even through a storm. Since then, she’s been meeting with the DOE, Sandia National Laboratories, PSE&G, the Board of Public Utilities, and renewable energy consultant Greener by Design to come up with a plan to put Hoboken, or at least a part of it, on its own power grid.
“We need to make sure whether it’s a cogeneration system or back-up generators, that we’re able to operate off the grid and through the storm,” Zimmer said.
Making Hoboken self sustaining is important, Zimmer said, because people in her town don’t evacuate.
“I’ve been told by housing authority residents, ‘Don’t even try to get us to evacuate.’ There are other people who just don’t have the resources to do it. I feel as an elected official, I need to help them be as safe, even if that means helping them shelter safely in place,” Zimmer said.
Designing the Microgrid
Hoboken’s microgrid project was announced last June, and since then, Sandia has been working on the scheme’s design, answering questions like which buildings would be on the grid, what kind of energy sources would power it, and how it would be turned on when it was needed. Earlier this month, Sandia gave the city an approximately 200-page draft report of its findings. City officials and their partners on the project are currently reviewing that report.
One of their first orders of business is to talk to the owners or residents of the 50-something buildings that will be connected to this self-sustaining grid. While the final list of stakeholders, is still to be determined, it is expected to include city hall, emergency services like police and fire, hospitals, senior housing facilities, tall buildings with elevators, a grocery store or two, and possibly some hotels and restaurants.
“Sandia’s plan looks at the right of ways now and maps out where this thing is going. As we meet with stakeholders and see who’s in, we’ll begin to get a picture on the ground,” said Adam Zellner, founder of Greener by Design. “We can’t connect everyone in this demonstration. But the mayor wanted to start with those folks who will be helpful to have during emergency situations, so folks can live and have energy and be in a normal environment.”
The draft report suggests powering the grid through a variety of energy sources, such as solar panels, wind turbines, and fuel cells, which are like large batteries that convert hydrogen and oxygen into water, and in the process, produce electricity. It would also use generators fired by fossil fuels like natural gas, such as reciprocating engines and combustion turbines. Some of the generators would be combined heat and power (CHP) units, meaning they not only generate electricity but also heat, which can be used as well.
Some of the power sources, like CHP, would be able to run either through the microgrid or through PSE&G’s regular grid, and in fact they would be running much of the time, in order to save the city money on energy. For example, during peak hours electricity produced by PSE&G might cost as much as 12 cents a kilowatt hour, while electricity generated by the CHP plant might cost about 9 cents a kilowatt hour. And if the heat produced by the plant is also put to use, the cost of CHP energy drops down to about 7 cents a kilowatt hour, experts say.
One Grid or Another
But while a portion of Hoboken will be able to obtain energy either from PSE&G’s grid or from its own microgrid, it can never use both grids at once. In fact, in order to turn one on, the other must be disengaged.
“It’s like two little lines that never touch and never meet. And once you throw a breaker, one will be totally on, and the other will be totally off,” Zellner said.
But with all the different sources of energy available, and the switches that will enable Hoboken to go from one grid to another, some experts say the design may be too complicated to work. It’s hard enough to leap from one power system to another, given that electrical voltage and frequency must always be maintained within a tight range in order to avoid power surges and dips. But Hoboken’s design involves about half a dozen power sources and two grids, making those transitions more complex, experts say.
And then there’s the matter of start-up costs. Putting just one CHP system into a hospital might cost $10 million. It might then cost another $10 million to install the wires and controls that would connect it to the microgrid, the source said.
“Who the hell is paying for this? My concern is the ratepayer in Hoboken going to pay for this, and if that’s the case, this exercise might be a huge waste of time,” said one energy expert upon hearing some details of the design. “Just to get the control architecture and the metering right could cost hundreds of millions.
Early estimates for the project are actually $30 million to $50 million, depending on what and how much the city can procure in grant money. The cost will vary, depending on the energy is ultimately generated and which buildings are incorporated into the grid. The energy savings achieved over time can make a unit pay off over time, but that’s not for years. Right now, for instance, it takes about five to seven years to get recoup the cost of a CHP system. Solar panels could take 10 to 12 years. And then there are parts of the grid that are just sunk costs, like storage, or, say, a diesel generator.