Essential in Energy Mix

Renewable energy will have an increasing role to play in responding to the challenge of climate change. In Australia and internationally, continued growth in renewable energy is forecast. This will occur, however, against a background of rapidly rising demand where renewable energy cannot keep pace. The cost and availability characteristics of most forms of renewable energy limit their practical use.

There is no single source of energy or technology that can wholly achieve the reductions in greenhouse gas emissions being sought by the community and policy makers. For this reason, the different solutions should be seen as complementary, and over the next fifty years, expected to come into play at different times. Renewables have been the focus of action for some time, yet the period beyond 2020 is when large-scale adoption of carbon capture and storage is tipped to occur.

Matching Supply and Demand

Perhaps the greatest challenge facing renewables is the mismatch between supply (as determined by nature), and demand (as determined by the customers). The answer lies in some form of energy storage technology. While hydrogen, generated from electrolysis of sea water, could play such a role, the cost would be considered prohibitive at this point in time.

Most credible analysis of renewable energy (principally wind) indicates that the maximum average share of the generating load which can be supplied is about 20%. At this level, peak production rates could approach 60% of demand and thus, issues of grid stability become of major concern. Only one developed country, Denmark, has approached this proportion of supply by renewable energy and that is facilitated by nuclear and fossil fuel base load generators in surrounding countries.