Material challenges in renewable energy

New research claims that, in the race against climate change, the renewable energy industry must embrace the circular economy. Matthew Stone of NextGen Nano, explains how energy companies can overcome this obstacle.

By 2050, the European Union (EU) aims to cut its greenhouse gas emissions by 80 to 95 per cent, compared with levels recorded in 1990. To achieve the targets outlined in the Paris Agreement, the EU has pledged to spend at least 20 per cent of its budget, up to the value of €180 billion, on technologies and research for tackling climate change.

The Netherlands is one country making great strides in the adoption of renewable energy on a large scale. It was the first country in 2017 to state that it wanted to phase out the use of natural gas by closing all coal plants by 2030, and it has also made plans to build several offshore wind plants.

While these steps demonstrate the Dutch’s positive transition to renewable energy systems, a report supported by the Dutch Ministry of Infrastructure has found that on a global scale this route may not be sustainable. In fact, the report claimed that “if the rest of the world would develop renewable electricity capacity at a comparable pace with the Netherlands, a considerable shortage [of materials] would arise.”

Many of the rare metals that are used to manufacture existing renewable technologies are mined from just a handful of countries. Europe is almost completely dependent on foreign supply of critical metals and as renewable energy productions scale up to meet demand, governments could be faced with several barriers.

So, considering the global supply of rare materials like those used in solar panels and wind turbines is insufficient for a full transition to a renewable energy system, scientists and engineers need to find viable substitutions for rare materials. Alternatively, global leaders need to embrace a regenerative approach to the design, maintenance and recycling of renewable technologies. This is also referred to as the circular economy.

Recent scientific breakthroughs in organic semiconductors have led to the creation of polymer solar cells that are not only more efficient, but that can also be used to make flexible, wafer thin and semi-transparent solar panels that can be designed to fit virtually any application.

For example, NextGen Nano’s PolyPower blends earth-friendly polymers with organic polymer solar cells (PSCs) to provide a lightweight, flexible and potentially inexpensive approach to solar energy harvesting. Notably, the technology achieves these characteristics while still being robust, mitigating the problems associated with traditional photovoltaic (PV) brittle panels.

These cells also solve another problem; they are Earth-friendly unlike silicon-based cells. The manufacture and disposal of existing silicon solar panels produces hazardous materials such as cadmium compounds, silicon tetrachloride, hexafluoroethane and lead. Moving to polymers makes the panels easier to recycle at the end of the panel’s usable lifecycle and reduces the environmental concerns surrounding these as a result.

Committing to reduce carbon emissions and fossil fuel usage is a bold decision for any economy to make, but it’s necessary for our global leaders to drive change and implement principles and methods of design that make it easier to manage current materials. The absence of long-term planning, with specific implementation plans for renewable energy capacity targets, creates uncertainty and undermines government credibility.

It’s fundamental that we find alternative or substitute materials in order to meet the increased demand of renewable technology across the world. For solar panels, making the transition to polymers will go a long way in mitigating this issue.

Matthew Stone is commercialisation director at organic polymer solar cell producer NextGen Nano