Episode one features architect Craig White, whose idea to make modular buildings out of straw bales could see homes and commercial buildings save 60% of their energy costs.

Episode two joins Maltese mountaineer & inventor, Marco Cremona, who stepped off a trek up the Himalayas into the thick of the competition with his idea to save precious water reserves by installing on-site waste water recycling plants in large hotels.

In episode three we meet Mathew Holloway, whose innovative air cooling system not only looks stylish, but is built from eco-friendly materials and uses just 10% of the power consumed by traditional air-conditioning systems, thus providing a potentially huge reduction in carbon emissions for buildings around the world.

In the last, thrilling episode, the three finalist's ideas are put to the ultimate test as CNBC's Steve Sedgwick hosts this tension-packed television event.