www . refrigerationandaircon . co . za RACA Journal I April 2024 43
Technical
From all accounts , the cost of LNG / LPG compares favourably with electrical power ( kg versus kWh , based on available information ). In this regard , international sources indicate that natural gas VRF systems produce substantially lower overall costs .
The cost of site establishment and safety requirements will surely prove of little consequence when taking into account the inconvenience of load shedding and power outages . It ’ s worth noting that an LNG / LPG gas storage facility would be more expensive to establish , since more space is required due to its larger volume .
As far as capital equipment costs are concerned , in South Africa we have no current supply source on which to make suitable cost comparisons . However , this could be easily ascertained through any one of the local major VRF equipment suppliers . To my mind , however , pricing should be reasonably competitive given the close similarity of the technology applied in both cases of electric-driven versus gas-driven VRF .
Before we all get too excited , there are some concerns , not with VRF technology but with the long-term supply of natural gas in South Africa , which could well be a serious future stumbling block . A BusinessTech article on energy ( 17 November 2023 ) alluded to a plunge in South Africa ’ s natural gas supply within the next three to four years , claiming that the shortfall could well trigger the country ’ s next economic crisis . A level of clarity is needed sooner rather than later as to where additional gas supplies can be sourced , if such a crisis is to be avoided . In the longer term , the supply prospects look more promising , with a new gas field discovered off the West Coast which could well be in operation by 2030 .
In conclusion , it ’ s good to know that a gas engine VRF derivative is available and is well developed . Whether or not it will suit South Africa ’ s alternate energy requirements going forward depends on a number of factors , factors that urgently require a decisive and fast-track approach by the powers that be .
On a personal note , I would like to see the development of a dual-drive VRF arrangement – a combined electrical / gas driven compressor ( s ) with an easy auto change-over system . However , this is probably wishful thinking on my part based on our country ’ s unique power supply situation and particular energy challenges .
In this regard , as incredible as it may seem , my wish has been granted . Hailed as a ‘ World First ,’ a leading Japanese manufacturer has successfully developed a gas / electric hybrid system , thus taking advantage of gas and electricity to achieve better energy savings . RACA
www . refrigerationandaircon . co . za RACA Journal I April 2024 43