The ‘Clean Air – A human right?’ campaign truck had a two-day spell at Canary Wharf as part of a European tour to champion the issue of clean air as a basic human right. Outside the Canary Wharf tube station, however, where the roadshow was located, there is no power supply available.
The organisers of the event, a joint venture between Camfil-Farr and Scania, were faced with the need to hire a diesel generator to power the energy-hungry promotion unit that requires a three-phase 32A supply to power lighting, AV systems, filtration fans and air conditioning plant.
There were initial concerns over suitability of the solution because of the substantial electrical loads. In practice the solution worked perfectly and the impact on reducing costs was significant and much greater than had been anticipated.
Before considering gridtogo™, a 40kVA generator was specified to run for the full 48 hour duration of the event. The large generator would have been needed to cover the theoretical maximum load presented by the starting characteristics of the a/c and the large three-phase fan motors, although it was quite feasible that this would never occur or, at least, for only the very shortest time.
A 15kVA three-phase version of gridtogo™was used together with a smaller 20kVA generator giving a nominal output of 35kVA which is capable of adding 200% of its rated output for 5 seconds (a total available output of 50kVA), it was more than capable of making up what was needed for peak power demand.
Typical of the data collected is that of system voltage and current. The graph shown below illustrates the typical load profile. The blue voltage line shows periods of generator running where the output voltage of the generator is slightly higher than that of gridtogo™.
For this application, solar PV was also introduced to the solution to provide an additional source of input and, although weather conditions were not ideal in this case, for a longer deployment where average energy needs are more modest, this can represent a significant contribution to the overall mix.
Had a 40kVA set been required and run for the full 48 hours, fuel consumption would have been in the order of 500 litres or more (based on 11 litres per hour). The 20kVA set ran for only 16 hours and consumed less than 80 litres. That is a straight saving of over 420 litres of fuel in 48 hours.
Based on the assumption that 1 litre of diesel produces 2.65Kg’s of CO2e, the solution produced 212 Kg rather than 1,113Kg – a saving of 901Kg’s CO2e. Employing gridtogo™ meant being able to dramatically reduce dependence upon a generator and enable the event to go ahead with the least possible environmental impact.
REDUCED MAINTENANCE COSTS
The reductions in generator running hours have other benefits, in longer deployments, refuelling visits are reduced and servicing costs are reduced and generator life will be significantly extended. All of these things represent further financial savings.
For the duration of the deployment, gridtogo™ was fitted with an optional monitoring device that collects data for system performance and is able to relay this to a web portal. It is then possible to view and analyse this data as well as monitoring system status, location and to be able to make adjustments to settings as may be necessary. Alarm and status conditions can also be relayed by SMS or e-mail to designated recipients. This could be a warning of low fuel levels or battery charge status for example.