100 tonnes of carbon has been displaced from the electricity supply by all the solar roofs owned by Community Energy Birmingham, since they were installed. We keep readings of how much power is generated and can then use the average carbon content of grid electricity from power stations to compare with our own zero carbon electricity. The four buildings where we have solar panels have had their carbon footprint reduced by 100 tonnes. Now that we have a large new  array at The Pioneer Group, Castle Vale, this carbon displacement effect should increase rapidly.