Conserving Resources, Renewing Energy
We consume more than the Earth can regenerate — and we're hitting that limit earlier every year. The energy transition is part of the answer. But it only works if we also think about the materials that wind and solar installations are made of. And what happens to them when they've reached the end of their life.
The Earth can no longer keep up. Forests, fish stocks, fresh water — humanity is taking more in a year than nature can replenish in the same time. Earth Overshoot Day makes it clear: our appetite for resources has grown far beyond what the planet can sustain. In 2026, we will have burned through our annual budget by July 30. A decade ago, that date still fell in August. Twenty years ago, it wasn't until October.
The biggest driver of our ecological deficit is the fossil fuels we continue to extract from the ground in staggering quantities — oil, coal, gas. Burning them releases enormous amounts of CO₂ that forests and oceans simply can't absorb fast enough. Which is why switching to renewable energy sources matters more than ever.
The direction is right. The pace is not.
This shift is already well underway. In 2025, global renewable energy capacity was more than double what it was ten years earlier — and it's picking up speed, according to the latest report from the International Renewable Energy Agency (IRENA). Solar is the biggest driver, with capacity up more than tenfold since 2015. Wind power has tripled over the same period.
The result: roughly a third of the world's electricity now comes from renewable sources. And renewables have long since taken over when it comes to new capacity — according to IRENA, they accounted for more than 85 percent of all newly installed capacity in 2025. Perhaps most striking: the cost of solar power has dropped by around 90 percent over the past fifteen years, making it the cheapest way to generate electricity in many parts of the world.
And yet — it's not enough. Because electricity is only part of the picture. Heating, transportation, industry — the vast majority of global energy demand still runs on fossil fuels, which account for around 80 percent of it. Every day we stick with this energy mix deepens our ecological debt: more CO₂, more resource consumption.
Wind turbines and solar panels need to be built to last
One factor often goes unnoticed: it's not just about how many new installations go up or how cost-efficient they are. It's also about what they're made of. The materials have to withstand extreme conditions, perform reliably for decades — and be recoverable at the end of their life. Without that, the energy transition is only half a promise.
A wind turbine is no simple piece of equipment. Its components are exposed to storms, salt, heat and UV radiation. That demands coatings that hold up. The connection between an offshore wind farm and the mainland has to work reliably — even on the ocean floor.
Solar installations face their own challenges: heat, humidity and constant sun exposure. And in battery systems, one of the biggest hurdles is protecting cells from overheating. None of this would be possible without high-performance plastics.
Specialized coatings, for example, protect rotor blades from wear at the leading edge — one of the most common reasons turbines fail prematurely. Seals and damping materials keep connections tight and absorb vibration. Rugged housings and frames shield the technology inside. Unglamorous, perhaps — but without these solutions, the rise of renewables simply wouldn't be possible.
Materials matter
Keeping these materials in circulation reduces the need for fossil raw materials. That means designing the plastics used in wind and solar installations from the outset so that they can be efficiently recovered, processed and reused in equivalent applications without any loss of quality. Circular plastics reduce the demand for virgin raw materials — and make energy installations less dependent on finite resources.
Covestro develops exactly these kinds of materials: protective coatings for rotor blades, elastomers for underwater cables, framing materials for solar panels. The company is working to bring these plastics back into the loop at the end of their useful life.
Because renewable energy and circular material flows have to be thought of together. Both are needed to reduce resource consumption, curb CO₂ emissions — and push Earth Overshoot Day back where it belongs: later in the year.