Marks and Spencer has reached its target of becoming "fully carbon neutral" five years after it launched its sustainability project, dubbed Plan A.

The UK retailer embarked on its Plan A sustainability drive in 2007, which set out 100 commitments to alleviate its impact on the environment by 2012. Two years ago, M&S added another 80 pledges it hopes to hit by 2015, with then chairman Sir Stuart Rose saying the company wanted to be "the world's most sustainable retailer".

In its "How we do business 2012" report, published today (7 June), M&S provided an update on the 180 commitments. It said it had achieved 138 and a further 30 are "on plan". However, the company revealed it has failed to meet six of its goals, while a further six are "behind plan".

The company revealed it is now "fully carbon neutral", having cut energy use by 28% through more efficient refrigeration systems, and counting renewable energy tariffs and offsetting.

The retailer also said that it now recycles 100% of its waste. Of food waste, 89% is used to generate energy in anaerobic digestors and the rest is composted.

The group emphasised the progress made on a number of social and environmental issues, ranging from energy saving and carbon emissions to waste management and the sustainable sourcing of fish.

Meanwhile, 31% of M&S products now have a Plan A attribute such as Fairtrade, organic or made from recycled materials. By 2020, M&S has set the target that all of its products will have at least one sustainable characteristic.

However, while the company has attempted to increase the penetration of Fairtrade products that it stocks in store, it has failed to convert a targeted 20m clothing products to the ethical certification due to "difficulties" in the supply chain. The group also failed to meet its target of tripling organic food and drink sales, reporting a decline in organic food sales since 2007 due to reduced consumer demand.

"I am proud of what we've achieved. We now have a better, greener and more ethical Marks & Spencer," CEO Marc Bolland said.

Bolland emphasised M&S's commitment to Plan A, which he said was part of the group's "DNA".

"Moving forward we will continue to engage customers in sustainable consumption," he said. "We remain as committed to Plan A as we have ever been. It is an essential part of our DNA and fundamental to our plans to become an international, multi-channel retailer."

M&S also suggested the move to improve efficiency and build a more sustainable model made good business sense. It claimed Plan A initiatives generated cost savings of GBP150m (US$233.2m) last year - up from savings of GBP70m delivered in the previous year.