In last month’s blog post I talked about the Climate Lens assessment framework for Canadian infrastructure projects. One of the interesting elements about this framework is that it requires a consideration of construction emissions. And I don’t mean emissions embodied in construction materials – which is an area that has been receiving attention for many years in the green building sphere, for example – but emissions actually released during the construction process itself.
Construction emissions in Canada are not insignificant, accounting for an estimated 6,000,000 tonnes CO2 in 2014 of direct emissions (according to this report from CIEEDAC that was prepared for the Canadian Construction Association). In addition, of course, there are also indirect emissions from the industry’s consumption of grid electricity.
However, emissions released during project construction are typically glossed over in GHG project accounting – either because they are deemed to be negligible over the project lifecycle and/or because they are deemed to be equivalent between the baseline and project scenarios. However, neither of these assumptions always holds true and for some projects, the construction emissions may actually be a significant portion of lifetime emissions – for example, on one infrastructure project that Firefly was recently involved in assessing for the Climate Lens, it is estimated that construction emissions will account for ~40% of lifetime emissions.
Most of the direct emissions from construction – around 68%, according to the CIEEDAC report - come from diesel consumed in heavy equipment and generators. Other emissions sources include items such as propane for site heaters, and gasoline for lighter vehicles.
Construction has been an area that has seen comparatively little improvement in emissions intensity (GHGs per GDP) over time – CIEEDAC showing a 12% improvement between 1990 and 2015, compared to an over 30% reduction in the Canadian economy as a whole (see Figure S-4, National Inventory Report 1990-2015).
However, within the last year or so there has been a run of announcements by manufacturers of major construction equipment, which indicate the electrification of this sector is finally commencing. For example:
CASE recently announced an all-electric version of their 580 backhoe, the 580 EV, which is now available to the market in North America
Liebherr has recently announced an all-electric concrete mixer and has a prototype all-electric drilling rig
Pon Equipment & Caterpillar have jointly developed a 26-ton fully electric excavator, which is currently available to markets in Scandinavia
Hitachi has a hybrid ZH200-5B model of its ZH200-A excavator, which it claims reduces fuel consumption (and thus GHG emissions) by 15%
With major manufacturers unveiling these projects, it’s clear that change is in the air (if you’ll excuse the pun) for the construction sector. As with passenger EVs, the environmental benefits of these machines are not limited to reduced GHG emissions, but also include reductions in local air pollution and noise – which are immediately tangible benefits not only to communities where construction is taking place, but also to the construction crews themselves. In addition, the manufacturers of these vehicles claim that the reduced operating and maintenance costs of these machines make them a better long-term economic investment than traditional, diesel-powered vehicles.
Whereas its likely that this equipment will face deployment challenges in remote locations that do not have access to grid power, we can nonetheless expect to see (and hear and smell!) a noticeable difference in construction sites around Canada as electrification of the construction industry takes off in the coming years.