Empire State is one of the most energy-efficient buildings in the world. Can others follow suit?

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To understand the carbon footprint of cities all over the world, just look at their skylines.

While industry and transportation have long been labelled as major carbon culprits, some environmental advocates are trying to raise awareness about another troubling source,especially in dense, urban areas buildings, the multi-level structures that fill many cities.

The amount of energy it takes to light, cool, heat and ventilate them can make up a large portion of a city's carbon output. According to a UN report, buildings around the world accounted for 37 per cent of energy-related carbon-dioxide emissions in 2020.

"In a city like New York, 70 per cent of our carbon emissions come from buildings," said John Mandyck, CEO of the Urban Green Council, a New York-based advocacy group that works to help make buildings more sustainable.

"We tackle the buildings, we solve the planet crisis," said New York Gov. Kathy Hochul, at an event on Thursday, unveiling a playbook to do just that.

The event was on the 80th floor, overlooking New York City's sea of buildings, the very problem that Hochul was talking about. But, more significantly, it was happening at the Empire State Building, whichmanaged to pull off an ambitious feat convert a building built in 1930 into one of the most energy efficient in the world.

"If we can make it happen at the Empire State Building, a historically preserved, pre-war icon, we believe we can make it happen anywhere," said Anthony Malkin, CEO of Empire State Realty Trust, the company that owns and operates the Empire State Building.

Goal to be carbon neutral by 2030

After a decade of implementation, the Empire State's ambitious retrofit hit a major milestone last year, reducing its carbon emissions by more than 50 per cent. By 2030, the goal is to be carbon neutral, said Dana Schneider, the director of energy and sustainability at the Empire State Realty Trust, in a news release.

The company is now releasing theEmpire Building Playbook: An Owner's Guide to Low Carbon Retrofits, filled with all the lessons of the last 10 years and their plans for the future.

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"Every single piece of this building, we've done something to make it perform better," said Schneider.

On the outside, the Empire State Building may still look as it did in the 1930's when it was breaking ground for its height and Art Deco design. But, it now runs in a way that would probably be unrecognizable to its original builders.

Take the triple-paned windows, with krypton and argon molecules injected into the air gap, for extra insulation. The building's 6,514 windows all got the upgrade. Heat loss in the winter months, and heat gain in the summer, are a huge problem for older windows that can drain a building's cooling and heating system.

"We reused 96 per cent of the original glass and frames, and we did it on a window factory we built on the fifth floor.Nothing left the building," said Malkin.

That project was completed in 2010.

In 2019, the building completed the world's largest elevator modernization project. All 68 of its elevators have regenerative braking systems. The elevators not only use less power to run, they also generate power as they go up and down, to power other systems in the building.

In the basement there's another key retrofit, the chiller plant, the centralized system that cools the air for a building. On the surface, Empire State's chiller plant may look as it did in the 1950s, but the software it now runs on will tell you otherwise.

"So we actually took out all the guts, recycled all the metal and built new guts to the chillers on site," said Schneider, who gave CBC News a tour of the building's essential energy-saving upgrades.

The new system can collect data and be programmed to cool the building's 300,000 metres of space with optimum efficiency.

'Not enough if we only succeed in the Empire State Building'

"Everything we learned here is given away, because it's not enough if we only succeed in the Empire State Building," said Schneider.

That's the point of the playbook, co-developed by the New York State Research and Development Authority (NYSERDA), the agency helping to lead the state's efforts to reduce greenhouse gas emissions by 85 per cent by 2050.

The playbook available online for anyone to use breaks down dozens of measures used by the Empire State Building already, plus hundreds of new ideas to support mass retrofits of buildings, including modernizing the electric grid.

"We are working with the 10 of the largest real estate companies in New York State, who own over 700 big buildings," said Janet Josef, a senior executive at NYSERDA.

Josef said that partnership has resulted in a commitment from owners to decarbonize more than 50 million square feet of their existing buildings within the next decade.The state's leaders are hoping their push will realize a projected economic impact of $20 billion US and 100,000 jobs if all buildings in New York follow the playbook.

"I say welcome to New York's energy future and as goes New York, goes the nation and goes to the world," saidHochul.

In Canada, 100,000 large buildings need retrofitting

In Canada, Prime Minister Justin Trudeau has called for a net-zero emission building code by the end of 2024.

The Canada Green Building Councilestimates that about 100,000 large buildings need retrofitting to help the country shrink its carbon footprint.

"The average Canadian probably doesn't know that buildings have a massive contribution to carbon emissions in this country," said Thomas Mueller, CEO of the Canada Green Building Council. "They focus on industry, they focus on cars. The fact is we need action in all three areas."

Some of that action is already legislated in New York. In 2019, the city passed a law that will require large buildings to cap their carbon emissions by 2024, the first municipality in the world to pass such a law.

WATCH | Vancouverreducingthe amount of fossil fuels used to heat buildings:

Vancouvers push for zero-emission energy sources in buildings

3 years ago

Duration 2:12

The City of Vancouver is joining a North American push to reduce the amount of fossil fuels used to heat buildings by making zero-emission energy sources a policy for new low-rise residential buildings.

Mueller says political will is important but so is private sector support.

"I want the 25 large commercial real estate owners in Canada to commit to decarbonize their entire building stock over the next 30 years," he said.

For the group gathered at the top floor of the Empire State Building, a day before Earth Day, the hope is for the playbook to reach far beyond New York and empower advocates, worldwide, like Mueller.

"You have the playbook, you have no excuses and you have history awaiting your actions here today," said Hochul.