People hoping to become the first in the UK to buy straw bale homes commercially will find out if they've been successful today.
There has been huge interest in the seven energy efficient properties in Bristol the sale has had to be conducted by sealed bids - they'll be opened later.
The seven homes in St Bernard's Road, Shirehampton, reduce heating bills by around 90 per cent and are being marketed at £220,000 for two bed houses and £235,000 for a four bed.
Experts at the University of Bath say the super-insulated houses can save up to 90 percent on the average household's heating bill.
The homes were built in just nine days thanks to Bristol-based ModCell's unique design of prefabricated straw bales sandwiched between timber frames, which slot together on-site.
The homes have been tested in simulated floods, fires and hurricane-force winds by the University of Bath.
Straw absorbs and stores carbon dioxide from the atmosphere as it grows.
The houses include rainwater harvesting provisions, LED lights, solar panels and an air-source heat pump to reduce bills further.