Most urban building involves concrete – and the cement industry causes more CO2 emissions than commercial aviation. How about climate-neutral wood? Berlin hosts a growing number of buildings using natural material.

It's everywhere. Hundreds of millions of tons are produced each year and plastic is in countless products and packaging. And as we know it doesn't go away once it is discarded. The world is drowning in plastic trash.

Everyone knows that we should save energy. But how is it actually done? And are the profits distributed fairly? Leading German climate expert Claudia Kemfert knows the dilemmas and explains the options.

The average German produces 500 kg of waste each year. Whole households end up in landfill. An alternative? Hamburg’s sanitation department sorts, reuses, repurposes, and resells discarded goods. But is it beneficial?

Worldwide, our desire to be online 24/7 generates billions of wasted kWh. How much does the average family consume as they live their daily lives? Why don't businesses invest enough in energy-saving technology?

Critical raw materials like lithium, rare earths and graphite are in high demand, but in most places they're not readily available. A team of geologists is working to find them in northern Europe - to allow the EU to be less dependent on China.

Smartphones couldn't exist without rare earths. They cause it to vibrate, for example, and display vivid colors. So rare earth elements are in huge demand worldwide. But mining them is difficult and bad for the environment, and reserves are finite.

People in Germany consume an average eleven kilos of chocolate each per year. But few think about the conditions under which cocoa beans are farmed. Child labor has been a problem for decades. But why? And what can be done about it?

The world is suffocating in plastic, but PET is an alternative to single-use plastic. Unisensor has developed sorting machines that can produce 100 percent pure PET flakes from recycled bottles. Could it help to beat the plastic problem?

Cities like Bangkok and Berlin could face flooding due to climate change. Bangkok faces rising sea levels and extreme weather. In Berlin, increasingly heavy rainfall is challenging drainage systems. The 'sponge city' idea could be the way forward.