A Standards Primer from SESSA's Trevor van der Vyfer
National standards are created by members of industry and not the Bureau of Standards which seems to be the common perception amongst the public. Having said that, South African national standards are also influenced by international standards.
The local standards body, SABS, does not sit down and prescribe to industry and the general public on what works and how things should be done. Standards for particular products are created by manufacturers, suppliers, and other party’s with vested interests sit around a table and decide what
components are required for that product.
SABS records and formalises what selected industry players have decided upon in specified meetings.
Issues such as operational safety, lifespan, strength and performance are decided upon at these working group meetings which are hosted by the standards authority.
The standard for electric geysers was first published in the 50’s when efficiency was not the main concern but rather issues such as electrical safety and design were of paramount importance.
The latest SANS 151ed7 published this week for fixed electrical storage water heaters has taken a bold step in South African history of by adding an energy efficiency label as a legal requirement to geysers. As of now all geysers sold in South Africa need to have a label fixed to the product
What this means to Joe & Jane public is, when purchasing a geyser electrical efficiency information must be available. Armed with price and availability informed decisions can be made by the purchaser. Previously geysers were bought on price and availability but now the efficiency of the geyser must be clearly displayed.
In terms of the SANS standards, standard domestic geysers, as used in conjunction with heat pumps and electrical connections are still 25% less efficient than dedicated solar geysers.
In time to come a minimum efficiency rating will be set and that the minimum heat loss between standard geysers and solar geysers be on par. Efficiency or thermal performance of an actual solar system is covered by a national standard.
The efficiency standard and thermal performance of heat pumps has yet to be created by industry.
Another important addition to the SANS 151 standard is the inclusion of polyethylene as a material for non-pressurised solar water heaters. Benefits of using this plastic material include extended lifecycle costs, local production and purpose made design.