LCA in transport infrastructure Part I: Life cycle thinking is one of those things – next to democracy, justice and education – that is a really good and useful thing to practice. You can read Part II here.
But be careful what you wish for. Going full life cycle may challenge your perception of what’s ‘green’ and what’s not.
Here are some surprising examples of what a life cycle assessment can reveal:
- Organic is seen as an environmentally friendly choice for food – but it often trades animal wellbeing for carbon emissions, or toxic pollution (from pesticides) for extensive land use.
- Electric cars seem better for the environment – but in Australia today, most electric cars are fuelled by black and brown coal combustion, which dramatically reduces the environmental advantages.
- Double-glazed windows reduce a building’s carbon footprint – but in areas where the climate is mild (e.g. only minimal heating and cooling are required), the embodied impacts in the manufacturing process (and materials mining) outweigh the energy savings.
Let’s agree on a few principles – as scientists would
Infrastructure may be one of the most suitable areas to optimise life cycle thinking. We are talking about assets that we build to be around for decades, even centuries. for infrastructure investments, it makes sense to take a complete life cycle approach. And before we get stuck in, can anyone remember the capital cost to build the Harbour Bridge in Sydney 1923. Let’s agree, to be ‘life cycle-optimised’, an asset needs to be:
- Triple bottom line-optimised. Social, environmental (or ecological) and financial, otherwise we potentially shift the burden from the environment to the financials, or from the financials to negative impacts on society (see: The Bottom Line Business Case for Sustainability in Infrastructure).
- Science-based and measurable. Otherwise how can we know where to start and what we have achieved (see: Sustainable Infrastructure: The Future is Measurement and EPDs).
- Relevant and ambitious. In other words, relevant to our Sustainable Development Goals and ambitious enough to meet local, national and international agreed targets.
So, what does life cycle thinking mean in practical terms for infrastructure projects? What does it mean for existing infrastructure and the infrastructure we build tomorrow?
Using these principles, we can deliver whole assets (transport, utilities, products) and individual assets (power plants, stations, car parks, depots etc.) that are modelled and optimised for their lifetime, rather than just in the construction phase. Specific sustainability initiatives can be evaluated from a cost/benefit perspective; as well as from the environmental and social performance that they deliver. This is leading practice and is the way to achieving positive change.
Thankfully, there’s a currency that quantifies the life cycle worth of green products – Environmental Product Declarations (EPDs).
We discuss more about EPDs and their role in infrastructure projects in Part II.