Carbon Action Project Launch Booklet - Page 8

2006. Reverse-cycle air conditioners were subsequently installed in the large and small halls although gas space heating was retained in the halls as well. As the cost of natural gas became increasingly greater and ACT’s pro- portion of renewable energy grew, it became evident that reverse cycle air conditioning was better than gas from both an environmental and an economic perspective. Although Ross Walker Lodge was designed to be energy efficient (with a 6-star energy rating), the long sequence of hot nights in 2018 con- vinced the residents and the Management Committee that air condi- tioning of the bedrooms and living area was desirable to provide a level of comfort to community standards. Individual room air conditioners were installed, resulting in some increase in electricity consumption, and although gas heating was retained its use has been significantly reduced. In 2019 the operating budget of Ross Walker Lodge allowed installation of a solar PV system to be considered to enable electricity consumption to be markedly reduced. Due to their reasonably favourable orientation, the 13kW of solar panels have been able to fully offset electrical con- sumption in the house for most daylight hours, and export as much or more than is being used. It’s too early to be accurate about the impact, but payback is expected to be less than 5 years, while ongoing electricity costs are halved. Mon- itoring over a full cycle of seasons will enable us to judge whether bat- teries should be added to extend the self-sufficiency and get better val- ue from the excess solar generation that is presently exported. The cumulative effect of 20kW of solar panels on the St Margaret’s property is to reduce greenhouse emissions by some 22 tonnes a year if the electricity produced displaces that from coal fired power stations in NSW. Although the ACT has now achieved 100% renewable electrici- ty, largely by commissioning wind and solar farms outside the Territory, the contribution of our 20kW enables more of that renewable energy to be available in the East Coast Network to displace the burning of coal. The following table gives an indication of numbers concerned. As both generation and consumption vary from year to year, typical results have been used. Carbon Action Project 5 1 March 2020