Just for fun. Bizarre scheme by the Crowne Plaza hotel in Copenhagen, Denmark, to either drum up publicity for its grand opening or provide a unique way of rewarding guests.
The new 366-room hotel in the centre of the Danish capital has installed specially designed exercise bikes in its fitness centre to allow guests to create electricity - the power is then ploughed back into the grid supplying the property.
Sound like a lot of hard work with no return, apart from a feeling of smugness at doing your bit for the city that hosted the recent Cop15 climate change conference?
As a reward for their endeavours, guests are given a complimentary meal (worth 200 Danish Kroner) when they generate 10 watt hours of electricity for the hotel every time they hit the bikes.
According to Crowne Plaza, a single guest cycling at an average of 30 kilometres per hour for 60 minutes will produce approximately 100 watt hours of electricity.
Amazingly, electricity generated by guests is stored in a battery and fed back into the main power supply of the hotel.
Not wanting to miss an opportunity to bring an iPhone into the programme, guests will be able to track their progress on the bikes via a dedicated app on handsets fixed to the handlebars.
The Danish government is clearly overjoyed. Deputy prime minister Lene Espersen says:

"I have no doubt that businesses that take an environmentally responsible approach have the edge over their competitors as leisure and business guests alike are increasingly choosing hotels based on their environmental credentials."