Cement and Carbon – The Pollution Vancouver’s Greens Politely Ignore
Vancouver council prides itself on being Green. Vancouver Council, especially the Green members and the pretend Green mayor want a subway. Their problem is, a subway consumes a lot of cement, which in turn creates a lot of pollution in the form of CO2 emissions.
Here we have a conundrum, in order to continue the masquerade of being Green by building a subway, you will produce a lot more pollution than if a subway was not built.
Cement Produces More Pollution Than All the Trucks in the World
ByThere are greener ways to make it, but customers are slow to embrace the change.
The most astonishing thing about cement is how much air pollution it produces.
Manufacturing the stone-like building material is responsible for 7% of global carbon dioxide emissions, more than what comes from all the trucks in the world. And with that in mind, it’s surprising that leading cement makers from LafargeHolcim Ltd. in Switzerland to Votorantim Cimentos SA in Brazil are finding customers slow to embrace a greener alternative.
Their story highlights the difficulties of taking greenhouse gases out of buildings, roads and bridges. After wresting deep cuts from the energy industry, policymakers looking to extend the fight against global warming are increasingly focusing on construction materials and practices as a place to make further reductions. The companies are working on solutions, but buyers are reluctant to pay more.
“There is so far too little demand for sustainable materials,” said Jens Diebold, head of sustainability at LafargeHolcim. “I would love to see more demand from customers for it. There is limited sensitivity for carbon emissions in the construction of a building.”
Significant Share
The cement industry’s CO2 emissions were more than all the trucks on the road in 2017
While architects and developers concentrate on the energy used by their buildings, it’s actually the materials supporting the structure that embody the biggest share of its lifetime carbon footprint. Cement’s contribution to emissions is especially immense because of the chemical process required to make it.
About two-thirds of the polluting gases that come from cement production stem from burning limestone. Kilns are heated to more than 1,400 degrees Celsius (2,600 Fahrenheit), about four times hotter than a home oven set to the self-clean cycle. Inside the kiln, carbon trapped in the limestone combines with oxygen and is released as CO2, the most abundant greenhouse gas.
A ton of cement yields at least half a ton of CO2, according to the European Cement Association. That’s more than the average car would produce on a drive from New York to Miami. And a single mixer truck can carry about 13 tons. Hundreds or even thousands of tons go into ordinary office buildings.
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There are low carbon concrete formulations (which includes cement plus aggregate) but and its a big but, it not only costs more, it takes a lot longer to cure and the minimum temperature for curing to occur is higher than standard concrete (between 5 and 9 degrees Celsius depending on the specfic concrete formulation used). This means in places like Canada, unless you find a way to heat the area where you are pouring the concrete, which is never cheap or easy, your construction season is shorter. Ottawa’s LRT project in Stage 1 fell months behind because it became to cold in the middle of October to pour concrete. Thus, huge amounts of building could not happen over the winter because concrete expected to be poured into forms in early to mid October didn’t happen until the following April.
You also now have to pay a fee for the low carbon concrete formulations, just like you sometimes have to pay chefs a fee to use their award winning recipes. This and other reasons has helped keep concrete prices rising at 2 to 3 times the rate of inflation and continually rising, every year since the mid 1990’s.
The ever rising price of concrete is one of the many reasons surface LRT is consistently cheaper than building below and above grade Skytrain lines. They use less, far less concrete than below grade tunnels and associated underground stations. The same is true for above grade prefabricated concrete Skytrain viaducts. You may want to build a Skytrain line extension from Surrey to Langley, all of it above grade on concrete guide ways.
The earlier stage 2 LRT Project from Surrey to Langley may have been slightly slower end to end but it was so much cheaper, easier and faster to construct because it was at grade in a segregated central roadway medium. That LRT line was less than $2 Billion to construct, the price included a satellite yard and the LRV’s. Now your paying $4.5 Billion for a similar length line plus the yard and the Skytrains aren’t even included in the price. The price of that Skytrain extension may still go up because you aren’t even in the request for proposal stage yet.
Two posts today, buy my god, i didn’t think that Kennedy Stewart was daft enough to promise a 19 km SkyTrain subway, from UBC to metro Town via 41st and 49th.
How much polluting cement will be needed for that?
As i said, tis the silly season, Skytrain here, skytrain there Skytrain everywhere.
Mind you, Social Credit Minister and free enterprise guru, Grace McCarthy once promised Skytrain to Whistler, back in the 80’s!