Energy problems: are they the same elsewhere?

Lorna Pelly
Gavin Fisher

A comparison between some renewable energy options for New Zealand and Scotland shows up some interesting similarities and differences.

The energy crisis in New Zealand in early winter 2003 demonstrated the danger of committing the majority of the national energy production to one resource, particularly one that can be affected by the climate. Having 70% of electricity produced from hydro-power makes New Zealand one of the leading countries in the developed world in renewable energy generation (see graph). However, one dry summer later, and the disadvantages of this are clear.

The immediate response to the crisis was to reduce energy use – that is, improve energy efficiency – encouraged by a major Government marketing campaign. Looking further ahead however, with a population that is steadily increasing and the Maui offshore gas field steadily decreasing, there is a clear need to get some stability into the energy market. The option of diversification of resources, particularly using renewable forms of energy such as wind and waves, provides a theoretically sound solution but in reality this has not happened. Why not?

We compared the situation for the future of some new renewable energy resources – wind, waves and tide – in New Zealand with that in Scotland to see if the same barriers were present. The intention was to determine if there were any particular economic, political, environmental or social problems that could be identified as restricting development, and if these appeared to be occurring internationally. Our main findings are outlined below.

Mixed-source energy

The most obvious comparison apparent from this study was the extremely high resource potential in both countries, but far more projects have come on stream in Scotland. In both countries there is a need for further energy resource development with demand increasing and big question marks hanging over the future of certain major resources.

In Scotland, one of the major growth obstacles came from the national grid. Exceptional wind, wave and tidal sites are all available around the west coast of Scotland and north into the islands. However, the demand is in the south and the grid was built to take power up to the north; it does not work well in reverse.

This geographical discrepancy may not be such a problem in New Zealand, but highlights the problems that the grid can cause. The construction of the national grid is biased towards large-scale fossil fuel stations that can be flexible in location; it does not cater well for smaller generators in awkward sites. Overcoming this will immediately add to the cost of possible developments, often making them appear uneconomic.

This is not to say renewable energy cannot be successful, but it is apparent that it is only effective as part of a mixed-source system. A community relying on one wind farm would suffer many days without power, but these peaks and troughs of power could be evened out by the storage ability of units such as hydro lakes. Hence, a well-balanced grid, rather than a grid dominated by large units, is crucial to the success of renewables.

Flexible energy market

The UK has flexibility in its energy market and would have many options if an energy crisis seemed imminent. It can purchase electricity by cable from France and natural gas can be piped in from Europe. There are some large oil and coal-fired stations that can be stoked up again and emergency gas-turbine stations that can be fired up within minutes. All these options are expensive, but it seems unlikely that power cuts would ever be a threat.

New Zealand does not have this “option comfort” and therefore does need to review the balance of the energy market. Whilst new renewable energy systems are far from ready to fill the gap of the Maui gas field, they could bring much-needed stability to the market through resource diversification.

Lorna Pelly and Gavin Fisher are based at NIWA in Auckland.