Many years before greenhouse gas emission reduction became a major driver for renewable energy development, New Zealand was an early adopter of several alternative energy technologies, particularly hydroelectricity and geothermal energy. It has achieved a level of 60% of total electricity generation from such sources, and is now pursuing a target of 95% of electricity generation from renewable energy, to be achieved in fifteen years. In recent years however the development of renewables has lagged that of other countries, particularly in fields such as wind power. The paper reviews the history, current status and potential of the major renewable energy technologies in New Zealand, and suggests what may be current barriers to development. It is seen that the likely major contributors to replacing fossil fuel based energy are likely to be wind power and expanded geothermal energy use, with biomass, marine and solar energy sources likely to play a lesser role. The barriers to development include environmental issues, the opportunity cost of biomass feedstocks, and a policy environment offering less incentive to RE development than is the case in many other countries.