This is the second blog on the subject of Managing Energy costs. It identifies the impact that the new Building Energy Management System (BeMS), which provides flexibility of management unachievable with the original controls, has had on propane usage. This is opportune considering the likely uplift in prices we will see once current contracts come to an end.
Metering on both propane boilers had been installed about 12months before COVID restrictions started to impact our activities. This allowed a model to be developed, using industry standard statistical techniques, of consumption versus its driver, the weather, in the case of space heating. Similarly for the water heating in comparison with water consumption.
The BeMS has now been installed for just 12 months and the COVID lockdown offered a prime opportunity to test its capability. The analysis, using the developed model, shows that space heating consumption has been reduced by 29,750 KWh and water heating by 10,500 KWh. This equates to £3160 at current propane prices and represents about 60% of the annual pre-COVID consumption. Also, the shower and toilet exhaust fans and the 2nd large heating boiler pump are now given over to the BeMS control functions. This has saved a further £300 in electricity costs at current prices.
The operational limitations of the original system would have only produced very limited savings during COVID lockdown and therefore the majority is due to the new BeMS. These savings represent a payback in about 16 months, whereas the original payback was calculated at about 3½ to 4 years. Further savings will become apparent in future due to much improved zonal and temperature control within the building.