The principal driver of today's impressive renewable energy growth is policy. Growth of renewables is strongest where and when the policy-makers in charge have established favourable conditions. Today, we can benefit from a rich set of policy experiences that have been made at national and local levels.

Policies to promote renewable energy existed in a few countries in the 1980s and early 1990s but began to emerge in many more countries, states, provinces, and cities during the period 1998-2005, and especially during the period 2005-2010. The number of countries with some type of policy target and / or promotion policy related to renewable energy almost doubled during this five year period, from 55 in early 2005 to more than 100 by early 2010.

Promotion policies for renewable energy will facilitate steady and sustainable growth of renewable energy market. Each policy reduces one or more key barriers that impede development of renewable energy, such as cost-related barriers, requirement for utilities to purchase renewable energy from power producer, as well as perceived risks in technical, financial and legal aspects.

Various international processes, such as UN conventions and programmes, G8 process and the high level ministerial conference series International Renewable Energy Conferences solely dedicated to renewable energy are the primary platforms to position and promote renewable energy as a potential win-win option in both the environment and development arenas.

Policies respond to specific national and local realities. There is not one kind of policy that fits in all contexts. Overview on Policy Instruments provides a commented guide to authoritative sources of information and lessons learned in implementing each instrument.