Backup diesel: what’s stored
Wesley Vale’s proposal includes 40 backup diesel generators, each holding up to 10,000 litres, for 400,000 litres stored on site (about 16% of an Olympic pool’s 2.5 million litres).ENV-19ENV-36 Bell Bay has 276 approved backup diesel generators.ENV-13ENV-14ENV-45 How much diesel Bell Bay stores, and how long either site could run on stored fuel, has not been disclosed.ENV-13ENV-14ENV-19
Real generators like these typically burn 406 to 528 litres of diesel an hour each at full load, and about 0.236 to 0.264 litres per kilowatt-hour produced. These figures come from four manufacturers' spec sheets for similar-sized units: Caterpillar, Cummins, mtu and Kohler. None is confirmed as the actual model at any Tasmanian site.ENV-60ENV-61ENV-62ENV-63 At Wesley Vale, 400,000 litres on site running at the site's full 52 MW would last about 29 to 33 hours. That is an estimate assuming all 40 generators share the load evenly, using generic burn rates.ENV-19ENV-60ENV-61ENV-62ENV-63
Bell Bay’s generators are capped at 24 hours a year, for mains failure, testing or emergencies. Council required an updated bushfire and emergency plan before construction, after Firmus corrected its generator count from 128 to 276.ENV-13ENV-14 Firmus has appealed the cap to TASCAT as “unreasonable”, wanting to use the generators to offset curtailment; the appeal is pending.ENV-45 Tasmania’s Bushfire-Prone Areas Code applies to land mapped as bushfire-prone. Both sites fall within this overlay: Bell Bay’s surrounding vegetation is mapped as dry eucalypt forest, adapted to fire, while Wesley Vale sits on modified farmland that is also mapped bushfire-prone.ENV-46ENV-65ENV-66ENV-68 Four of the six confidential proposals have no published location, so whether they would fall within the overlay is unknown.COM-02COM-03 The one named among them, the former Liberty Bell Bay smelter, is mapped bushfire-prone.ENV-65ENV-68
Fire danger itself is projected to rise. A downscaled regional climate model for Tasmania projects at least 120% more Very High Fire Danger days a year by 2100, over more than twice the area, with the fire season starting at least a month earlier. The weather pattern behind Tasmania’s worst fire days is also projected to become more frequent. Both figures are model projections to 2100, validated against observed weather for 2002-2012.ENV-98ENV-100
Nothing requires a data centre to run a fire service of its own. An aerodrome over 350,000 passengers a year must have a rescue and fire fighting service.ENV-94 A major hazard facility — a refinery, say; Tasmania has none operating — must keep fire-fighting equipment and trained staff on site for first response, handing suppression to the fire service.ENV-97 The National Construction Code asks a building only for hydrants and sprinklers, and those are for the fire brigade’s use.ENV-96
Tasmania’s State Emergency Service does not fight fires; its bushfire role is limited to support functions such as evacuations, traffic management and logistics.ENV-69ENV-70 In 2022-23 the Tasmania Fire Service employed 518 staff, of whom 353 were career firefighters, and it relies heavily on volunteer brigades.ENV-69 For scale, a 2021 fire at the Victorian Big Battery near Moorabool required more than 30 fire trucks and about four days to bring under control, and a 2021 fire at OVHcloud’s Strasbourg data centre required 115 firefighters and 44 vehicles, with the building destroyed regardless.ENV-71 ENV-72