What is green hydrogen, and how green is it, anyway?

Hydrogen, specifically "green hydrogen," has been making headlines in Nova Scotia in recent months as a handful of companies continue pursuing energy projects.

But the term is fairly new to many.

Even Nova Scotia's minister of natural resources and renewables, Tory Rushton, said in August that "green hydrogen wasn't in my vocabulary a year ago."

So, what exactly is green hydrogen? And how green is it, anyway?

Green hydrogen basics

Green hydrogen is hydrogen that's produced from renewable energy, such as wind or solar power.

It is produced using a process that may take you back to high-school science class.

An electric current is passed through water, which is comprised of two hydrogen atoms and one oxygen atom. That process, called electrolysis, separates the hydrogen atoms from the oxygen atom.

In green hydrogen production, the source of the electrical current must come from a renewable source; otherwise, it is not considered "green."

The hydrogen gas is then captured and can be stored for later use or channelled into a fuel cell to produce electricity. Some uses of green hydrogen include powering vehicles, planes, ships, long-haul freight and production of ammonia for fertilizer.

Green hydrogen is viewed by many as an environmentally friendly alternative to fossil fuels because it is generated using renewable sources such as wind energy, so it doesn't produce harmful emissions and can be stored.

How environmentally friendly is green hydrogen?

But some analysts caution there are caveats.

The first step in any green energy strategy should be efficiency — to use less energy, says Gretchen Fitzgerald, the national programs director for Sierra Club Canada.

"The best power plant is the one you don't have to build," she says.

The second step should be using the energy from renewables as a direct power source, rather than converting it to other products such as hydrogen, Fitzgerald says. Every time energy is converted from one form to another, it loses efficiency. 

However, green hydrogen is useful as a way to store renewable energy, for those times when the wind isn't blowing or the sun isn't shining.

A third consideration should be to use renewable energy as close as possible to the place it is produced, rather than transporting it elsewhere, says Brenna Walsh, the energy co-ordinator at the Ecology Action Centre.

"Nova Scotia still has one of the grids that is the most dependent on coal across Canada, certainly. And we think that just decarbonizing our energy system for our own use is really important," Walsh says.

She also cautions that if pipelines are used to transport green hydrogen, there is a risk of leakage.

Analysts also weigh the environmental impact of the renewable energy source used to produce hydrogen.

Walsh says any land-based wind projects should be sited with the ecological and cultural significance of the area in mind. There must be consultation with Indigenous people. Benefits to the local community, and community-owned projects should also be prioritized over for-profit projects, she says.

As for offshore wind, Walsh says infrastructure should not be sited in marine-protected areas, and proper consultation must occur with fishing communities.

Fitzgerald echoes that sentiment, adding that the federal government needs to create a regulatory body for offshore energy that is fair and balanced, with community consultation. She says the Canada-Nova Scotia Offshore Petroleum Board is responsible for conflicting duties, including promoting industry and protecting both the environment and worker safety.

Is Nova Scotia producing green hydrogen?

Not yet, but there are at least two proposals to watch on the horizon.

EverWind Fuels filed its environmental assessment documents to the province on Friday for its proposed project. The company plans to start making hydrogen at the former NuStar oil and gas storage facility in Point Tupper, N.S., starting in 2025.

The company wants to use water from nearby Landrie Lake to produce the hydrogen, which it will then convert into ammonia.

EverWind has agreements to ship 500,000 tonnes of ammonia per year to each of two German companies, Uniper and E.ON.

While the company is focused on exporting ammonia in the short term, CEO Trent Vichie says the facility could eventually provide hydrogen for use in Nova Scotia as sustainable aviation fuel, or to power fuel cells for vehicles.

The company hopes to build 300 wind turbines in "remote" areas of Guysborough County as the source of renewable energy for its products. But Vichie says if the green hydrogen plant is ready before the turbines, EverWind will draw on the Nova Scotia Power grid until the turbines are functional.

That's a concern for critics.

"This cannot be a greenwash," says Fitzgerald. "It has to be genuinely produced by wind, solar, geothermal, actual green energy that's put in the right place."

Vichie says by 2025, when the project may need energy from the Nova Scotia power grid — which uses both coal and renewables as energy sources — about 70 per cent of the grid will be powered by renewables.

"I would say like it'll be relatively minimal over time, what we're trying to take from the grid. And so, yeah, it'll be a combination of wind with balancing services."

Other green hydrogen plans

Another green hydrogen project that's been floated for Nova Scotia is a plan by Bear Head Energy to build a green hydrogen and ammonia production, storage and loading facility, also in Point Tupper. The project would be located at the site of the previously approved Bear Head LNG facility.

That project has not yet been submitted for environmental approval.

According to the Natural Resources and Renewables Department, two other hydrogen developers — Fortescue and Northland — are interested in export projects, while Eastward Energy and Port Hawkesbury Paper are interested in domestic production and use.

The province recently decided which companies will be awarded which pieces of Crown land for potential onshore wind projects that would feed into green hydrogen facilities. 

Those awards have not yet been announced publicly. More information is expected to be released by the Natural Resources and Renewables Department next week.