This is a very different matter from outline planning permission and as the name suggests, the fine details of the design are ironed out at this stage. This can in some cases be very detailed indeed. For instance, if you want to build in an existing conservation area it will probably get right down to the exact type of door knocker you want to use.
Planning law and policy has largely lost the lead in terms of green design for a number of complex reasons. Suffice to say that planners (and possibly society in general in the UK) have a very half hearted attitude to eco-build. It's a kind of 'Grand Designs' type anomaly which doesn't carry much weight with mainstream thinking. Don't expect to be treated particularly kindly unless you are in some kind of government designated 'high priority' category.
Occasionally you hear of people building a house without planning permission. This is usually very unwise. You can apply retrospectively but the chances are there will be some aspect of what you have built which does not comply and at that point you may find you don't get a lot of sympathy from either planners or councillors.
To get an idea of what is acceptable design you can try looking around at buildings in the same locality. For instance if there are houses in the same street with the same number of stories, similar features and similar building materials then there is a fair chance you can do something similar.
An exception to this is when an area suddenly changes from street to street. For instance there might be an area of old Georgian housing right next to another area of 1970s housing. Possibly the Georgian housing has been designated as a conservation area which is very strictly controlled as to what you can and cannot build whereas it might be possible to build anything you like in the 1970s area.
If you are employing an architect they will probably advise you on this; if not then it is worth going along to have a brief chat with the planners at your local council office. They are usually very helpful about telling you what kind of approach they think is acceptable.
When you put in an application a notice is fixed in a prominent place near the site in question so that neighbours are made aware of your possible intentions. They can then write in with objections (or even letters of support) to the planning department. It is of course quite common for neighbours to object because they quite like to take their dog for a walk on that bit of empty land. The planners have to weigh up which objections carry weight and which are just nimby (Not In My Back Yard). They do this by consulting other council officers such as highways, strategic planning, conservation, tree conservation, etc.
When planning permission is given it usually comes with a set of conditions and these are usually quite heavily peppered with clauses about road traffic including sight lines and parking.
see also the government Planning Portal site