Structuring uncertainty management for energy savings calculations

Abstract

South Africa has committed itself to reducing its greenhouse gas emissions. A key strategy to minimise the greenhouse gas intensity involves using incentivised energy efficiency initiatives. In South Africa, one of these energy efficiency incentives is Section 12L of the Income Tax Act, which rewards claimants with 95c/kWh for verified energy efficiency savings linked to the reduction of greenhouse gas emissions. This verification is done using the SANS 50010 standard, which requires the management and quantification of the uncertainty associated with reported savings. The accurate quantification of energy efficiency savings is therefore critical, and highlights the need for uncertainty management to ensure accurate and fair results. Although uncertainty quantification and management methods are already available, the correct and consistent application of relevant methods for specific uncertainty contributors is important. In this study, a solution in the form of an uncertainty quantification and management flowchart was developed to quantify and manage energy efficiency savings uncertainties. This tool incorporates a five-step approach towards energy efficiency savings quantification, and was applied to three industrial energy efficiency case studies. It was found that uncertainty levels can range between two and 18 per cent, due to varying uncertainty contributors. This highlighted the need for a structured approach pro-actively to identify, quantify, and manage uncertainty contributorsSuid-Afrika is daartoe verbind om kweekhuisgasvrystellings te verminder. Energie effektiwiteit word dus aangemoedig om kweekhuisgasvrystellings te verminder. In Suid-Afrika, is artikel 12L van die inkomstebelastingwet een van hierdie aansporings vir energiedoeltreffendheid. Dit beloon eisers met 95c/kWh vir geverifieerde energiebesparings. Die verifikasie word gedoen aan die hand van die SANS 50010-standaard. Dit vereis die bestuur en kwantifisering van die onsekerheid verbonde aan gerapporteerde besparings. Die akkurate kwantifisering van energiebesparings is dus van kritieke belang en dit beklemtoon die behoefte aan onsekerheidsbestuur om akkurate en billike resultate te verseker. Alhoewel metodes oor onsekerheidskwantifisering en -bestuur reeds beskikbaar is, is die korrekte en konsekwente toepassing van veskillende metodes ook belangrik. In hierdie studie is ʼn oplossing in die vorm van 'n vloeidiagram ontwikkel om onsekerhede rakende energiebesparings te kwantifiseer en te bestuur. Dit behels 'n vyfstap benadering en is toegepas op drie industriële gevallestudies. Daar is gevind dat onsekerheidsvlakke tussen twee en 18 persent kan wissel weens verskillende onsekerhede. Dit het die behoefte aan 'n gestruktureerde benadering beklemtoon om onsekerheidsbydraers te identifiseer, te kwantifiseer en te bestuur