Nothing beats coffee from a capsule machine in terms of convenience. And yet coffee pods require - and waste - more resources than all other methods of making coffee. Is there no way to make coffee that's both sustainable and convenient?

French press and filter coffee are great, but if you're in a hurry, capsules are the way to go - you have warm, steaming coffee in seconds. But what's the catch?

Many coffee capsules are made of aluminium. "It's the most environmentally unfriendly coffee capsule there is," says Thomas Fischer from consumer group Environmental Action Germany (DUH).

Fischer describes the energy-intensive process: First, bauxite ore, from which aluminium is made, is mined. Large areas of land are dug up for mining, natural areas are destroyed and toxic chemicals are used. "Red mud is a byproduct of the process. It's contaminated with heavy metals and doesn't get disposed of, but is stored in a collecting basin," Fischer explains.

The metal has to be melted down later, which "requires a huge amount of energy and is anything but climate-friendly." According to Fischer, disposable aluminium capsules produce up to 25 times more packaging waste than comparable products that are reusable or big packs of coffee.

A more environmentally friendly alternative to coffee pods is coffee from a French press. It's also great for making cold brews in the summer. — Photo: Fabian Sommer/dpa

In some countries consumers can separate coffee capsules and dispose of them in bags or dustbin containers that are then sorted for recycling, or they can even sign up for a special capsule recycling programme.

They may think they then have a clean conscience, but there is a catch. Recycling coffee capsules is not easy. According to Thomas Fischer, capsules are made from new material, including leftover punching material from the production process.

Fischer compares it to making biscuits or cookies: "You have the biscuit dough, cut out the biscuits and there is some left over. You collect the rest of the dough, roll it out again and cut out more biscuits, but it's still the same dough."

However, you can't make new capsules from old ones. "You need a sufficiently high aluminium content for coffee capsules." But this is not the case with materials collected as part of recycling schemes.

In Europe, there are around 450 aluminium alloys that contain different amounts of foreign metals such as copper, zinc or magnesium. If packaging from the recycling bin is melted together to form cast aluminium, the proportion of aluminium is often too low and the proportion of foreign metals is too high to make new coffee capsules.

So although the capsules are recycled, they are then used for other products. The aluminium is used to make bike or window frames - so it is not completely lost.

The good news is there are alternatives. Although plastic capsules are generally better than aluminium, they are still ecologically questionable. Coffee pads are an alternative to capsules - but you'll need a compatible coffee machine. Pads made from a fiber-based material can be disposed of in the organic waste.

According to Fischer, caution is advised when it comes to capsules made of bioplastics that are marketed as being biodegradable. Manufacturers claim that they can be disposed of in the organic waste or in the home compost - but this is not true.

The capsules do not break down easily. "With the exception of small rubbish bags, bioplastics are generally not allowed in the organic waste bin, as composting plants have problems with residue-free decomposition," Fischer explains.

There are specific reusable products that can help: plastic or metal capsules that can be refilled with ground coffee and reused again and again. The same principle applies to reusable pads.

This not only saves resources, but also money. The reusable options are compatible with most coffee machines. – dpa