On January 12, 2024, England’s new BNG policy came into force, via an amendment to the Town and Country Planning Act.

This requires property developers to ensure that, once their projects are complete, the developed area sees a 10% net gain in biodiversity. Essentially, developers must go a step further than preserving and replacing any biodiversity that is lost through development—they must actually improve it.

BNG shares the key principle of carbon offsetting: that should make up for the damage humans have caused the planet. But the policy is careful not to fall into the traps that have victimized commercial carbon offsets, and so proves that meaningful steps toward net zero can be taken.

Over the last few years, development has become a very contentious topic in the UK. A housing crisis has been brewing in the country since the start of the post-war period, according to the Centre for Cities. At the start of 2023, Britain had a backlog of 4.3 million homes compared to the average European country—a deficit that will take over 50 years to rectify, even with ambitious targets.

But despite this startling demand, many potential property developments have been struck down by “not in my backyard†(NIMBY) sentiment. One reason for this is the widely held idea that development, particularly the building of flats and houses, necessitates the destruction of greenspaces and nature. But a new piece of legislation from Natural England aims to blow this assumption out of the water.

BNG will promote nature recovery and offset England’s carbon emissions.

BNG is a new regulation for property developers, which ensures they not only preserve the natural environment and habitats for wildlife but actually improve it. The developers must first produce their own biodiversity gain plan, explaining how they will increase biodiversity both on-site and off-site. Next, an approved ecologist will assess the site’s biodiversity—using a new biodiversity metric—before and after the development takes place. The increase in habitats for nature must be secured for at least 30 years.

The benefits of this policy stretch across many areas. In terms of nature, habitats will become more joined up, helping native plants and animals thrive. The knock-on effect will hopefully be an improvement in human health and wellbeing, as greenspaces become more abundant and urban areas become greener and more pleasant places to exist. Improving biodiversity can also have positive effects on the economy, creating long-term income opportunities in habitat management and increasing the value of the country’s natural capital. Finally, the restoration and protection of nature can help to mitigate climate change by working to offset humanity’s carbon emissions.

The era of traditional carbon offsetting is over

On top of these advantages, BNG also provides an alternative to the dubious practice of commercial carbon offsetting. Carbon avoidance offsets are where companies pay to prevent carbon emissions in areas unrelated to their own business activities. For example, a European tech company pays to prevent deforestation in the Amazon rainforest.

There are many issues with commercial carbon offsets. Despite being used by more than half of the world’s largest listed companies, they are often criticized as being a license to pollute. On top of this, 2023 saw a scandal where the leading offset provider was found to have not planted 90% of the trees they were paid to.

England’s BNG policy shares the key motivation of carbon offsets—reducing our negative impact on the planet—but goes about it in a far more measurable and effective way.

BNG sets us up for more meaningful climate action

The most obvious difference between BNG and commercial carbon offsetting is that carbon offsets are merely meant to make up for a firm’s carbon emissions and achieve neutrality. Biodiversity Net Gain, however, clearly requires a net gain. This will make the policy more effective, as it simply goes further to achieve its goals.

Secondly, it focuses on end results, rather than just starting processes. Developers will have only fulfilled the requirements of BNG once a 10% increase in biodiversity has actually been achieved and secured for 30 years. Carbon offsets, in contrast, are supposedly successful once a new tree is in the ground, regardless of how much carbon is still in the atmosphere.

Finally—and most importantly—Biodiversity Net Gain is state-mandated. Companies might believe it is the moral (and customer-appeasing) thing to do to buy carbon offsets, but this is not a certainty. When it comes to English developers’ impact on nature, however, they do not get a choice.

The way that Biodiversity Net Gain deftly avoids the pitfalls of the carbon offset industry shows that effective and measurable climate mitigation policy is possible. Once it has had time to mature, the success of BNG will provide a guide for future approaches to climate mitigation and the push towards net zero.