A peak in global energy-related emissions could be achieved as early as 2020 if governments implemented five key policy measures, the International Energy Agency (IEA) said on Monday.

In its new ‘World Energy Outlook Special Report on Energy and Climate Change’ study, the IEA noted that this “major climate milestone” could be achieved by using only proven technologies and policies without changing the economic and development prospects of any region.

Intended as an effective bridge to further action, the five measures focused on increasing energy efficiency in the industrial, buildings and transport sectors; reducing the use of the least-efficient coal-fired power plants and banning their construction, and increasing investment in renewable-energy technologies from $270-billion in 2014 to $400-billion in 2030.

The IEA also suggested that fossil fuel subsidies to end-users be gradually phased out by 2030, while methane emissions in oil and gas production should be reduced.

Further, the IEA noted that for the United Nations Conference of the Parties (COP21) to be successful, four key pillars would need to be implemented. These included setting the conditions to achieve an early peak in global energy-related emissions, reviewing national climate targets regularly to test the scope to raise ambition over the next five years, translating the world’s climate goal into a collective long-term emissions goal and establishing a process to track achievements in the energy sector.

Global greenhouse-gas (GHG) emissions from energy production and use were double that of all other sources combined, meaning that action to combat climate change had to come first and foremost from the energy sector.

“As IEA analysis has repeatedly shown that the cost and difficulty of mitigating GHG emissions increases every year, time is of the essence.

“It is clear that the energy sector must play a critical role if efforts to reduce emissions are to succeed. While we see growing consensus among countries that it is time to act, we must ensure that the steps taken are adequate and that the commitments made are kept,” emphasised IEA executive director Maria van der Hoeven.

For countries that have submitted climate pledges for COP21, the proposed strategy identified possible areas for overachievement. For those that had yet to make a submission, it set out a pragmatic baseline.

The IEA report highlighted the need for climate pledges for COP21 to be viewed as the basis from which to create a “virtuous circle” of increasing ambition and advocated, as its second pillar, a five-year review cycle to test the scope for further action.

“Both the situation and the solutions are evolving rapidly – the world’s shrinking carbon budget means that any delay in taking action can be costly, while the pace of energy sector innovation means that a five-year review would allow national targets to keep up with events and help build investor confidence,” the IEA advised.

As its third pillar, the IEA recommended that the goal of keeping the increase in the long-term average global temperatures to below 2 °C also be expressed as a long-term GHG emissions target, making it more straightforward to apply in the energy sector.

“Doing so would help anchor future expectations, guide investment decisions, provide an incentive to develop new technologies, drive needed market reforms and spur the implementation of strong domestic policies, such as carbon pricing – all of which are necessary to meet the 2 °C goal,” it noted.

The final pillar proposed by the IEA report was that the COP21 agreement establish a process for tracking progress in the energy sector.

“Tracking national progress would both provide clear evidence of results, reassuring the international community that others are acting diligently and identify countries that are struggling with implementation, enabling assistance to be provided if needed,” the IEA highlighted.

In recognition of this need, the report set out appropriate metrics to monitor energy sector decarbonisation.

IEA chief economist Faith Birol stressed that any agreement reached at COP21 had to have the energy sector at its core or risk being judged a failure. “Climate pledges submitted for COP21 are an important first step to meeting our climate goal and our report shows that they will have a material impact on future energy trends.”

Collectively, countries accounting for about two-thirds of global energy-related emissions had either formally submitted their climate pledges, or intended nationally determined contributions (INDCs), for COP21, or had discussed their possible content.

A first assessment revealed that these pledges would have a positive impact on future energy trends, but fell short of the major course correction required to meet the 2 °C goal.

“The assessment of the INDCs shows that the growth in global energy-related emissions [will] slow but not peak by 2030. The link between economic growth and emissions [will] weaken significantly but is not broken: the economy grows by 88% from 2013 to 2030 and energy-related carbon dioxide emissions [increase] by 8%.

“Renewables are the leading source of electricity by 2030, but inefficient coal-fired power generation capacity declines only slightly. Such findings underline the need for ambitious national pledges for COP21 that can act as a solid base upon which to build stronger action, such as those enabled by a transfer of resources,” the IEA stated.