What does the city of Chelmsford have in common with the London 2012 Olympic Games?

The answer is that they both required 35 million kilowatt hours to operate, although one used that much over the course of a year and the other used the same amount in just one month.

The Olympic Games watchdog, The Commission for a Sustainable London 2012, has today published its post-games report, attempting to quantify the sustainability efforts of the London 2012 Organising Committee (LOCOG).

The Commission concluded the Games broadly delivered against its key environmental objectives, and is on track to meet targets to send zero waste to landfill and ensure 70 per cent of waste is re-used, recycled, or composted.

However, the report also highlights a number of concerns, particularly around energy management.

“Games-time” carbon savings of 20 per cent delivered through a reduction in energy use are on track to be achieved, the Commission said. However, it said it was “disappointed” with LOCOG’s last-minute development of a comprehensive energy plan, which limited the potential for further carbon reductions.

The Commission said LOCOG was on track to exceed its target to reduce energy consumption by 20 per cent compared to a business-as-usual baseline, given that energy savings were implemented in the design process.

However, it found on visits to the site that 40 per cent of venues were not implementing LOCOG’s energy saving plan, and that energy was being wasted at 80 per cent of the venues, with lights left on during the day or vehicles idling when stationary.

The report also accused the Olympic Broadcasting Service (OBS) of refusing to save energy, and using too many generators, even when pressed by LOCOG officials to curb unnecessary energy use.

“OBS is a major energy consumer and took no part in conservation activities despite LOCOG’s efforts to engage them,” the Commission said.

“Gross overestimates of energy consumption, particularly from OBS, led to unnecessary deployment of generators. This was only partly resolved during the Games as energy managers identified excessive generator capacity through daily reviews of data.

“[But] more accurate estimates would have led to generators not being hired in the first place.”

The report also found there was “minimal use” of alternative fuels, with more than 90 per cent of the energy supplied from fossil fuel sources.

LOCOG was forced to scrap a target to deliver 20 per cent of its energy from renewables back in 2010, because plans for a 2MW wind turbine fell through. It also failed to deliver a low carbon fuel for the Olympic cauldron.

LOCOG’s partner, EDF, ran out of time for testing a new biofuel based on Miscanthus, and was forced to pull its plan over fears the flame would extinguish and prove a source of embarrassment for the organisers.

However, the Commission said it was impressed by the modular design of the cauldron, which allowed for the flame to be turned down to just 75 per cent of its full capacity. At 16 tonnes, it also weighed a fraction of the 300-tonne cauldron used during the Beijing Games.

The Commission has now urged the UK to ensure that future Olympic Games hosts learn from London’s successes and failures.

“London 2012 has raised the bar on sustainability, not just for future Olympic and Paralympic Games but for industry, and for the organisers of major events the world over – from music festivals to football World Cups,” said Shaun McCarthy, Chair of the Commission for a Sustainable London 2012.

“By being open to learning from these successes as well as the missed opportunities, future major projects could even out-perform London 2012’s sustainability achievements.”