On 28 March 2022, the United Nations Environment Programme United for Efficiency (U4E) initiative and the Southern African Power Pool (SAPP) convened a meeting with Southern African power utilities and distribution transformers focal points who sit on Integrated Demand Management Working Group (IDMWG) to discuss the development of minimum energy performance standards (MEPS), and the use of the new U4E total cost of ownership tool, for distribution transformers.

The objective of the meeting was to feedback on draft distribution transformer MEPS and the opportunities for their implementation in a harmonized manner across the region.

Transformers are a critical part of the electrical infrastructure of a country. They help to improve the efficiency of the transmission and distribution of electricity by increasing and decreasing the voltages in the network as necessary. Although transformers themselves are highly energy-efficient, typically with efficiency values greater than 97%, there are still significant improvements in efficiency that can be made which are very cost effective and utilize mature, proven and reliable approaches.

Research has shown that around 5% of all electricity generated is lost due to distribution transformers across the African continent, and that a transition to the most energy-efficient transformers could save 5.7 TWh/year, worth 400 million USD, by 2040, with an associated reduction in CO₂ emissions of 4.7 million tonnes yearly. In addition to saving energy, state-of-art distribution transformers can contribute to improved grid stability, energy security and energy access and reduce the pressure from distribution and transmission losses on already strained networks.

With this in mind, U4E has supported the development of draft MEPS for distribution transformers which are targeted to serve as a recommendation for policy implementation to the eight countries with Green Climate Fund (GCF) Readiness projects in the Southern African region (Botswana, Eswatini, Lesotho, Malawi, Namibia, Tanzania, Zambia and Zimbabwe).

The draft MEPS, which are based on the U4E model regulation guidelines for distribution transformers, propose three levels of minimum efficiency standards to be phased in over several years. This phase-in takes into account the long planning horizons for distribution transformers, allowing local/regional suppliers time to make the necessary changes, while giving a schedule of expected performance improvement over time to utilities and suppliers alike.

As with other products and appliances, the first cost of a distribution transformer is not fully representative of the total cost of ownership, which includes the cost of both purchasing and operating the transformer in a national network. Because of their long in-service lifetime (30 years or more) it has been shown that the running costs (i.e., electrical energy losses in the transformer) can be as much as four times higher than the purchase cost (i.e., first cost) of a transformer.

For this reason, the International Electrotechnical Commission (IEC) has developed a total cost of ownership (TCO) methodology which capitalises the value of future losses and incorporates them into the purchasing decision process. The TCO methodology can be applied to any transformer size, from small distribution transformers right through to large network and transmission transformers. To complement this, the U4E publication, A Guide to Using Total Cost of Ownership When Purchasing Distribution Transformers, and supporting Excel spreadsheet, provides information on, and guidance for, applying this IEC methodology to inform the purchasing decision process and help to ensure that utilities and companies purchase and install cost-optimised and energy-efficient transformers into their network.

The Southern African region is no stranger to harmonised activity on the transition to energy-efficient products. The Green Climate Fund (GCF) Readiness projects in the Southern Africa also include a component on leapfrogging the markets in the eight participating countries to energy-efficient refrigerators. In addition, a regional EAC-SADC project, funded by the GEF, the Clean Cooling Collaborative (formerly K-CEP) and the UK Government (Defra) aims to develop a policy framework for energy-efficient and climate friendly refrigerators and air conditioners, with the ultimate goal to develop regionally harmonized MEPS and labelling for these products in both regions.

An update on both these projects was provided as part of this meeting to give context to the current co-operation in the region on development of MEPS and implementation of a harmonised approach.

If you are interested in further information on the event, or on the draft distribution transformer minimum energy performance standards that were discussed, please contact Madeleine Edl at madeleine.edl@un.org.