PRP pledges to be ‘carbon negative’ by 2050 PRP has become one of the first major architecture firms to declare it will be carbon negative by 2050 Advertisement The pledge to become ‘carbon negative’ means it will need to find ways to remove more CO 2 from the atmosphere than it emits, going one step further than ‘carbon neutral’, whereby emissions are balanced by carbon savings made elsewhere. The practice follows in the footsteps of tech giant Microsoft, which raised the stakes in January 2020 by announcing it would be carbon negative by 2030 and offset all the carbon emissions it has made since it was founded in 1975.