Appledore Island’s lessons in renewable energy
On Appledore Island, the challenges and opportunities of solar and wind are already playing out
About 10 miles off the coast of New Hampshire, there’s a little island that could be a snapshot of what our future on the mainland might look like when it comes to renewable energy.
Appledore Island is home to the Shoals Marine Laboratory, run jointly by the University of New Hampshire and Cornell University. But it’s also a laboratory of sorts for engineering a grid that runs on a high percentage of renewable energy – a place where the challenges and opportunities of using lots of solar and wind are already playing out, years ahead of the mainland.
Appledore isn’t connected to the mainland’s electricity grid, which means the remote island has to be self-sufficient when it comes to generating electricity. The island runs on what’s called a microgrid, a self-contained system where the electricity being produced by solar panels and a wind turbine has to be carefully balanced with how much electricity is being used: for running lab equipment, keeping the fridge cold, purifying drinking water, or just turning on the lights.
Now, a big chunk of the island’s energy needs are met with renewable energy, but that wasn’t always the case. In fact, through the mid-2000s, the laboratory was entirely powered by a diesel generator, which was both costly and a source of the kind of emissions that are driving global warming. But between 2007 and 2019, the lab reduced the use of diesel by 90 percent. This summer, the solar panels provided about two-thirds of the island’s energy consumption, the wind turbine provided 11 percent, and diesel made up the remaining 22 percent.
That transition away from fossil fuels and toward more renewable sources of energy is one that’s relevant for the rest of the country in light of the Biden administration’s announcement earlier this year setting a goal of a net zero emissions economy by 2050. And by 2030, the administration is aiming to reduce greenhouse gas emissions by around 50 percent.
Appledore is a case study in what working toward these goals actually entails.
There’s some good news for a so-called clean energy transition. For one, the lab’s executive director, Jenn Seavey, said that other remote communities on a microgrid should take note of the potential savings: renewable resources have been cheaper than buying 10,000 gallons of diesel fuel.
“Our sustainability program actually started as a way to save money,” she said. “It’s much cheaper for an isolated community, a small community, or a community who wants to take control of their own power.”
But the island also offers a caveat to green energy advocates pushing for 100 percent intermittent renewable energy. While the island had been aiming for 100 percent, Seavey said she’s now reconsidering that in light of new information about just how many batteries it would require. The cost, she said, would be “ridiculous.”
“We’ve been constantly having this debate about what it is we’re aiming for,” Seavey said. “Really, it’s probably going to be around the 90 percent mark.”
Martin Wosnik is an engineer who works with the laboratory and teaches about renewable energy at UNH. In general, he said, getting to two-thirds renewable energy through conserving energy as well as solar and wind isn’t too hard, but after that threshold it starts getting more difficult – with the last few percentage points becoming the most challenging.
To use only intermittent renewables would mean building out a vastly oversized storage system, he said. Those batteries would be overkill most of the time, but they would be needed on a rare week, when the wind wasn’t blowing, for instance. So instead of creating a massive battery bank, the island will likely continue using the diesel generator to get through those times.
But increasing renewable generation on the island is only one part of how they’ve weaned themselves off fossil fuels. Another huge piece of the puzzle is conserving energy. Half of the island’s reduced reliance on diesel is due to conservation efforts – using less energy.
Conservation efforts are already underway on the mainland through incentives like rebates to buy energy-efficient appliances or light bulbs. But the state has held up a triennial plan that would increase energy efficiency efforts in the state.
Wosnik said this is an area where there’s room for meaningful improvement in New Hampshire.
“Most people in New Hampshire could actually do a lot more in terms of energy conservation if they knew what in their household actually consumed a lot of energy,” Wosnik said.
For Seavey, working and living with the microgrid means those on the island are acutely aware of how they are using energy. If a researcher wants to bring a new piece of equipment, for example, they instantly think about how much power it will draw and what percentage of the overall power that is.
“We look for the most efficient thing,” she said.
When something is plugged in on the island, Seavey said, it then appears on a live dashboard.
“So it’s very clear in that kind of setting what your contribution is to this precious energy resource,” Seavey said.
Seavey said when she went to her home on the mainland, she swapped out all of her lightbulbs for LED ones, and she turns lights off compulsively when she’s not using them.
Finite amount of energy
At about 95 acres, Appledore is the largest of the Isles of Shoals. It’s part of the town of Kittery, Maine, which hugs the New Hampshire border. No year-round residents live on the island, although there are a handful of private homes on the island’s southern edge. Twelve buildings make up most of the Shoals Marine Laboratory campus, which operates only during the summer. There are a few dorms and a building for staff housing, as well as office space, teaching labs, classrooms, and research facilities.
In a small system like Appledore, it’s clear that there’s a finite amount of energy available – there’s only so much sun, wind, and battery capacity. And once that’s depleted, it means the generator has to turn on. But there are also times when the sun is shining and the wind is blowing, and there’s lots of energy to spare. And that’s where water comes in.
On the island, potable water is another finite resource. Running a reverse osmosis machine for drinking water takes a lot of energy, which is why it makes sense to run it when there’s excess energy coming onto the grid.
On the mainland, Wosnik said linking water and energy makes sense, too. Moving water and wastewater treatment are among the most energy intensive and expensive items on a New Hampshire town’s electricity bill.
“Energy related to water can be done at different times, when the energy is available,” Wosnik said. And water can be used to store energy, by moving it up into a water tower when intermittent resources are available, and that energy can later be released on demand.
Wosnik said this is a design question – matching high electrical demands associated with water with intermittent renewable energy – that New Hampshire municipalities should be encouraged to ask.
One New Hampshire electric utility has gotten involved in what’s going on at Appledore, where many of the engineering challenges are similar to those on the mainland.
Alec O’Meara, a spokesperson for Unitil, said the same questions on the island about integrating renewable resources are the ones the utility is dealing with when it comes to monitoring the mainland grid as it both puts power out to people’s homes and now, increasingly, receives energy from things like rooftop solar arrays. Electricity is coming into the system from different places, which O’Meara described as a two-way street.
“That is the paradigm shift that you’re moving toward and away from this idea of the top-down, one location that is sending the electricity out across the entire district,” O’Meara said.
But that transition means the electrical grid needs to be brought into the 21st century, another area where the state has stalled. In 2015, the state started working on a grid modernization docket at the Public Utilities Commission. In 2020, the commission issued an order that would have moved the process forward, but the state’s largest utility, Eversource, argued the order took too much control away from the utilities, an argument Unitil supported. Now, over a year later, that docket is still open and pending before the utilities commission.
Wosnik, who is originally from Germany, said the grid modernization is needed. Updates would allow significant amounts of energy to move over long distances – something that’s currently limited.
“Sometimes it’s quite a shock what qualifies as the electric grid here,” he said.