Of all the EU regulations to shape UK policies, environmental directives have been some of the most controversial. Three of the most significant are those on green energy, recycling and air quality - all of which pose a challenge for the UK. What might Brexit mean for the UK in these policy areas?

1. Green energy

What EU green energy targets does the UK have to meet?

It's the bête noire of anti-wind farm campaigners: the EU Renewable Energy Directive (RED).

The directive requires the UK to generate 15 per cent of its energy from renewable sources by 2020 - up from just three per cent when the directive was adopted in 2009. That's not just electricity but also energy used in heating and transport.