Lufthansa and SWISS are looking to help passengers to offset their CO2 emissions by purchasing sustainable air fuels. The program had been in a test phase, however, Lufthansa and SWISS are now rolling the scheme out across their booking systems.

In the age of flight shaming and increasing emphasis placed on the effects of flying, airlines across Europe are implementing schemes to allow passengers to offset their CO2. In fact, some airlines are making this mandatory on domestic bookings. Lufthansa and SWISS are the latest to take part by bringing the Compensaid platform to their booking portals.

Lufthansa touts the new program as the "world's first online platform of its kind". However, despite the spotlight being on sustainable jet fuel, it seems that the other option of reforestation has proved to be more popular thus far.

326.33 tonnes of CO2 have so far been offset through the programs reforestation option. This compares to just 59.78 tonnes offset via sustainable jet fuel. So far €42,392 has been paid into to the scheme.

Sustainable fuel or reforestation?

Passengers using Lufthansa's new Compensaid platform have two options for offsetting their CO2. They are able to choose a mixture of the two options. The sustainable jet fuel is the more pricy option, while reforestation is around one-twentieth of the cost. The fuel option costs €1 per liter, while each tree costs around €3.90.

However, while the sustainable fuel option is more expensive, Lufthansa also advertises that the Sustainable Air Fuel offsets CO2 "immediately". However, this does not mean what you think, as it could take Lufthansa up to six months to feed the sustainable fuel into its operations. This means that the sustainable fuel you purchased won't be on your flight.

On the other hand, the reforestation option, while cheaper, is not instant. In fact, should a passenger choose to offset 100% of their CO2 via that option, it will take 20 years for the CO2 to be offset. If the offset is split 50/50 between the two options, it will only take 10 years to offset the carbon emissions.

How does it work?

Next week I'm going to be flying with Lufthansa from London to Frankfurt. With this in mind, I decided to take Lufthansa's brand new platform for a spin. Upon landing at the Compensaid website, you are greeted with a big Lufthansa Yellow button inviting you to offset your flight. Clicking this takes you to a page where you can enter your flight details.

Once you have entered your flight details, you are taken to a page where you can decide how much to invest in each program. In my case, investing 100% in sustainable fuel would cost €39.56, while choosing reforestation costs just €1.91. Both options would offset 81kg of CO2.

I opted to go for 5% to Sustainable Fuels and 95% to reforestation. While I was keen to purchase some fuel, I think in the long run reforestation is better as it will keep offsetting CO2 once my 81kg has been offset. This bought me 1.98L of sustainable jet fuel, in addition to 0.46 of a tree. As such, Lufthansa says it will take 19 years to offset my CO2.

On the next page, I was prompted to enter my payment details and then was dumped on to a thank-you page informing me that my carbon emissions would be offset in 19 years' time. I also instantly received an email with three attachments. One certificate for my sustainable fuel, one for my purchase of half a tree, and thirdly a receipt for my half a tree in German.

Will you use the platform to offset your carbon emissions? Let us know your thoughts in the comments.