Grimshaw architects (the team behind the Eden Project in Cornwall, pictured below) are planning to turn a Lancashire rubbish dump into a tropical rainforest which would heat itself with decomposing garden and kitchen waste.

The “Kew of the North” project could become a tourist site to regenerate a large area of derelict land. It includes a huge waterfalls, walkways through the treetops and possibly Europe’s biggest compost heap, capable of using most of the green waste of a city the size of Manchester.

Grimshaw is developing the idea of the Georgian pineapple growing sheds at the Lost Gardens of Heligan in Cornwall. These are heated by bark and horse manure and grow up to 300 exotic vegetables and fruit.

The architects would build walls out of rubble, which would contain “bio-digester” composting tubes. Into these would be fed household and municipal waste. Heat exchange tubes would then transfer heat emissions into the glass-roofed space to create the warm, saturated environment needed for rainforest life. Besides the resulting thousands of tonnes of compost could be sold and would reduce the amount of peat dug up.

Kew of the North is expected to get its fuel for free and would run at a profit even without visitors. Engineers estimate that it could earn about £12m a year by generating heat and electricity on site and from taking the green waste.

Via archinect The Guardian.