Unite said union reps should also have the right to examine information on a firm’s impact on the environment to help “green” workplaces.
The union surveyed 10,000 members in the electronics and computer industries and found that more than four in five believed energy was wasted in their offices and factories.
Almost all those questioned said unions should be involved in helping cut a workplace’s impact on the environment.
Unite called on employers to offer more cycling facilities for their staff, offer loans to use public transport and allow staff to work from home.
The union added that company executives should have their pay and bonuses linked to meeting environmental performance targets.