Premier Inn, Tamworth, Staffordshire
Whitbread is the UK's largest hotel chain but this is its first "green hotel", which it says is a "test bed for sustainable technologies". Ground-source heat-pumps cool and heat the 20-room hotel and restaurant, and the company says the solar panels provide energy to heat water for 1,000 baths a year. A similarly green 60-bedroom hotel in Burgess Hill, Sussex, is due to open in the autumn.
0870 242 8000, premierinn.com Doubles from £39 per night, room only.
Hotel Sigiriya, Sri Lanka
In the shadow of the Unesco Lion's Rock fortress, this 79-room hotel could have been the last thing this ancient citadel needed, but the sensitive design means it fits in with the landscape. There are all the creature comforts you'd expect, yet it has taken significant steps to keep its emissions to a minimum, including the installation of a gasifier to replace diesel, card key switches provided for air-conditioning, and recycling water to irrigate the gardens.
+94 662 284 811, serendibleisure.com Doubles US$62.
Apex Hotels, UK
A small chain of smart hotels in London, Edinburgh and Dundee that has done more than most to green up its act, from installing energy-saving insulation to using ozone in its swimming pools instead of chlorine. Judge Stephanie Draper of Forum for the Future said: "Their efforts sound like a lot of things every hotel should be doing anyway, such as replacing light bulbs or turning off TVs at night, but they have taken things a step further with green roofs and energy reducing technology – they even have a green architect."
0845 365 0000, apexhotels.co.uk From £56 per room per night.