However, the regime had produced "perverse incentives" and had contributed to a 79 per cent increase in ACOT revenues flowing back to DG owners in the last eight years, the authority's chief executive, Carl Hansen, told a media briefing today.
In some cases, such as the lower South Island, DG was actually adding to the pressure to spend money on upgrading the grid because the new plant was being installed in areas where there was excess electricity generation capacity already, which had to be exported out of the area,
In other cases, investment in grid upgrades raised the value of ACOT payments to DG generators, creating an unintended incentive to install DG.
However, the authority has not gone as far as its original proposals, reducing the cost of the proposals to DG owners by some 55-to-75 per cent, said Hansen.
The concerns of small DG operators had been heard and there was still potential to earn ACOT revenues where Transpower judged DG plant genuinely relieved pressure on the national grid. In future, Transpower would be able to contract for that capacity. It would undertake a four-stage review of DG plant, starting in the lower South Island next April and moving through the rest of the country over the following two years.
The authority also did not proceed with a proposal to remove the regulated price ceiling for what local electricity distributors could charge generators to connect to their networks, another concern expressed by DG plant owners.
The decisions have no impact on solar rooftop generation at a household or small business level.