Carbon footprint miscalculated

Water companies have blasted a report supplied recently by the British body that monitors carbon footprints for erroneously reporting that desalination plants accounted for a third of Cayman’s rising carbon emissions.

The report presented at a recent climate change conference in Cayman seemed to reveal that the islands’ desalination plants were responsible for 350.5 kilotonnes of the 925 kilotonnes of carbon dioxide emissions recorded in 2007.

The Department of Environment, which supplied the raw data that was then analysed by UK company AEA Technologies, admitted that the information had not been interpreted correctly.

The water companies – the Water Authority, Cayman Water Company and Consolidated Water Company – claim that the production of water in the Cayman Islands amounted for only 4.6 per cent of electricity used to produce the water and that their contribution was counted twice in the report.

Lisa-Ann Hurlston of the Department of Environment’s Sustainable Development Unit, said AEA had neither confirmed nor disputed the water companies’ assertions that their output accounted for only a fraction of what they had originally calculated.

‘It is important that AEA recognised they had made incorrect assumptions about the desalination plants’ use of onsite power generation… While this would account for double counting of that portion of electricity already captured in the total energy consumption figures we get from CUC and Cayman Brac Power & Light, it still does not adequately explain the margin of error created which nearly equated the desalination sector emissions to those of the energy sector,’ she said.

The original report showed that the water and electricity industry in the Cayman Islands each accounted for about a third of the 925 kilotonnes of CO² in 2007.

Ms. Hurlston said the AEA still needed to clarify what other assumptions have been made in the data interpretation. ‘We have a number of other data gaps and clarifications to hash out with them in an effort to improve upon the inventory this year, so I do not anticipate that we will have definitive results any time soon.’

A revised report sent to the Compass has simply removed data involving desalination plants, and now shows that Cayman’s carbon footprint rose from 281 kilotonnes of carbon dioxide in 1990 to 574 kilotonnes in 2007, with electricity accounting for 372 kilotonnes of the CO2 emissions in 2007.

The DoE collects data from Cayman’s Economics and Statistics Office on energy usage and production in Cayman and passes that along to AEA Technologies, the consultancy company that compiles an annual inventory on the UK’s greenhouse gas emissions.

In a joint letter to the Caymanian Compass, the water companies stated: ‘Based on our estimate that in 2007, the production of water required 28 million kilowatt hours of electricity and that 604 million kilowatt hours was generated by the electricity providers, the production of water would take about 4.6 per cent of electricity.’

They went on to say that this meant desalination of water could not account for one-third of the country’s carbon emissions, as stated in the original report.

While they acknowledged that they contributed to the islands’ carbon footprint, ‘the data presented was inaccurate and led to the wrong conclusions’, the letter read.

Ms. Hurlston acknowledged that the misinterpretation of the data was unfortunate, but she said it was ‘at least comforting that we have never before had this level of communication with them, despite many request in years past for them to provide whatever figures they had for the Cayman Islands and to query information given them to ensure emission estimates ‘look right’ for the size of the country, economy, population, etc.’

She added: ‘While we are disappointed that AEA cannot provide updated desalination emission estimates at this time, we would rather they take the time to get it right than provide us yet again with misinformation.’

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