OPINION: Nuclear power has lower carbon emissions than coal-fired electricity, but nuclear produces toxic waste that must be stored for centuries. This risks an environmental disaster.

Wind turbines are also low carbon but face another issue – the massive blades made of composites need replacement every 10 to 20 years. They cannot be recycled, repurposed or even crushed by a bulldozer.

Thousands of blades are simply buried every year and will sit in the ground pretty much forever. For nuclear and wind power the need to bury the waste is a bad environmental outcome.

This shows the challenge, that steps we take to ‘go green’ can create other problems which are often unseen or unexpected.

Let’s take electric vehicles (EVs).

Sourcing components for batteries requires lithium and cobalt which can be mined in the Congo and other undeveloped countries.

Human rights issues – in terms of working hours, working conditions, fair pay and child labour – are serious and largely hidden problems. Environmental issues – with landscape turned into wasteland and widespread impacts on water quality – are storing problems for future generations.

The problem for EVs gets bigger, as their production generates more carbon emissions than the manufacture of a petrol car.

However, over its full lifetime an EV will have lower carbon emissions than a petrol or diesel car. This benefit can vary, for example in New Zealand the majority of our power is renewable and generated from hydro, while burning coal generates around 50 per cent of Australia’s power.

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An EV is a low emission vehicle but in many countries can be powered by a high emission energy source like coal.

EV manufacturers strive to make as much of a vehicle as possible recyclable at the end of its economic life. Yet here’s the final challenge with an EV, there is no getting round the fact that battery disposal is a problem.

An EV’s lifecycle has several environmental and human rights issues from sourcing cobalt through to battery disposal. This illustrates that green solutions are seldom perfect, but are preferable to not trying at all to be more sustainable.

The key here is progress through innovation, changes in behaviour and new technology bringing constant improvements.

While the massive wind turbines – which can be the length of a rugby field – are currently buried at the end of their life, there is innovation.

Vestas, a huge Danish wind turbine manufacturer just announced its discovery of a way to fully recycle wind turbine blades. The blades can be broken down into base components and then repurposed into a new blade.

Great news, another step forward.

Yes there is a ‘dark side’ to many measures we take to become greener, especially when these solutions involve complex new technologies and global supply chains.

What we are looking for is innovation to take us from the ‘dark side’ of being green to simply being ‘dark green’.