Construction on the first of the new towns could start in 2016
Two new areas - in Devon and Hampshire - have been added to the proposal list for a second string of so-called "eco-towns" by the government.
The schemes in Cranbrook, east of Exeter, and north Fareham will each receive £200,000 to develop plans for green housing and infrastructure.
East Devon District Council plans an initial 3,500 homes, housing and planning minister John Healey said.
Fareham Borough Council wants to create at least 7,000 homes.
Ministers also unveiled an overhaul of planning policies to ensure green measures, such as electric car charging points and renewable energy schemes get the go-ahead in new developments.
The new schemes join nine local authorities already developing plans for environmentally-friendly new settlements.
The first four developments were announced for Norfolk, Oxfordshire, Whitehill-Bordon in Hampshire and Cornwall in July.
In December, the first five of the second wave of plans were unveiled by authorities in Lincolnshire, Leeds, Coventry, Taunton and Yeovil.
They are sharing a £10m pot to help them bring forward their proposals.
A further £10m has been announced for councils to train staff to give them skills to develop environmentally-friendly housing and energy sources.
Mr Healey said the government hoped to see 10 new environmentally-friendly settlements built by 2020.
The project was intended to meet housing needs and tackle climate change, but has been dogged by opposition from local communities.
Fears were raised that it would bypass local democracy - despite government assurances the planning process will still have to be followed.
Protesters also claim the new "eco towns" could have an impact on transport and jobs.