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Renewables – now 70% by 2050 is the low estimate!

by Dave Elliott

In a joint report, the International Energy Agency and the International Renewable Agency present their views on how to comply with the Paris COP 21 Climate protection aims. The pathways that they describe both have renewables expanding rapidly, but differ in pace and level. As might be expected, IRENA sees renewables as being able to deliver significantly more power by 2050 than the IEA – 82% of global electricity by 2050, compared to the IEA’s estimate of ‘near 70%’. However, it is striking that, whereas previously, renewables had often been seen as perhaps able to deliver 50% by 2050, we have now moved on to debating whether 70% is too low. With costs falling, the supposed limits are being pushed back continually…The difference between the IEA and IRENA estimates for renewable electricity amounts to around 10,000 TWh, and seems to be mainly due to the strategic orientation of these two organizations. As the report notes, ‘the modelling analysis conducted by the IEA aims at laying out a pathway towards energy sector decarbonisation that is technology-neutral and includes all low-carbon technologies, taking into account each country’s own circumstances. The analysis conducted by IRENA maps out an energy transition that stresses the potential of energy efficiency and renewable energy sources to achieving the climate goal, while also taking into consideration all other technologies’.

The IEA sets the scene as follows. It says ‘limiting the global mean temperature rise to below 2°C with a probability of 66% would require an energy transition of exceptional scope, depth and speed. Energy-related CO2 emissions would need to peak before 2020 and fall by more than 70% from today’s levels by 2050. The share of fossil fuels in primary energy demand would halve between 2014 and 2050 while the share of low-carbon sources, including renewables, nuclear and fossil fuel with carbon capture and storage (CCS), would more than triple worldwide to comprise 70% of energy demand in 2050’.

In its previous reviews, the IEA has been somewhat circumspect about the potential for renewables to expand rapidly, for example suggesting, in a summary of their World Energy Outlook 2016, that, on current policies, by 2040 only 37% of global power generation would be renewable electricity, up from 23% now.

However, that seems to be their most pessimistic view. In their enhanced ‘450’ scenario, they said that nearly 60% of the power generated in 2040 might come from renewables, around half of that from wind and solar. And in the new joint report with IRENA, they say it could expand to nearly 70% by 2050. That still leaves plenty of room for other low carbon options in electricity supply, and also for heat and transport: they say that, together, renewables, fossil CCS and nuclear could aim to meet 70% of global energy demand by 2050.

IRENA, however, is even more optimistic about renewables. In the joint report it says they could supply 82% of global electricity by 2050 and 65% of global primary energy. As a result, energy-related carbon emissions could, it says, be reduced by 70% by 2050 and completely phased out by 2060, with renewables and efficiency accounting for 90% of emission reduction, with 10% achieved by fossil fuel switching and CCS. But CCS would be deployed exclusively in the industry sector. Very different from the IEA, which sees CCS playing a key role in most sectors. IRENA also see nuclear as marginal: it would stay at the 2016 level, whereas the IEA has it expanding, though not much – renewables dominate.

In either case, it’s a massive expansion of non-fossil energy. IRENA says by 2050 an extra $29 trillion of investment would be needed, equivalent to 0.4% of global gross domestic product (GDP). But it should provide stimulus that, with other policies supporting growth, would boost global GDP 0.8% in 2050. And it says reducing the impact on human health and mitigating climate change would save between two- and six- times more than the costs of decarbonisation’.

What next? As renewables improve, IRENA may feel more confident in proposing even higher projections, more in line with NGO views that renewables could reach 90-100% of electricity and maybe even of all energy by 2050. Indeed, Lappeenranta University of Technology (LUT) in Finland has produced an ambitious global study of renewable potentials, with hourly balancing, which says 100% by 2030 globally is technically viable and affordable.

The Lappeenranta study does push things to the max in many cases, but its detailed modeling offers convincing evidence that renewables can deliver very high contributions in the EU and elsewhere, with surplus output stored or traded and used for balancing. Though maybe not 100% by 2030!  For the EU part see   whilst a NE Asian extension, with HVDC supergrid links is at  and

Energy Matters had a go at denting this model, and initially came out as seeing it as wildly unrealistic. Certainly it does rely on some spectacular incremental improvements (and taller wind turbines), and long distance trading of excesses, the latter assuming that local demand peaks and supply surpluses elsewhere can be matched. That may not always be the case.  But a second review by EM concluded that, if all that was accepted/condoned, it might just about be credible to get to high renewable shares. Though there were still some big caveats on the realism of the wind input.

In the UK case, with over 100GW of wind in the LUT scenario, there would be occasional need for imports and/or inputs from storage, but the latter could use the big excess produced from wind at times. So EM’s Euan Mearns fell back on arguments like this: ‘Parts of Scotland are already despoiled by the deployment of wind turbines and I do not want to see this environmental vandalism spread’. Seems that some of the opposition has had to abandon technical and economic arguments. And with offshore wind getting cheaper by the day, the land-use argument may carry less weight. For their part LUT came backs with this reply.

The debate continues, but with the belief that high levels of renewables are possible now being more central, although it’s still being challenged: see my next post. But for what it’s worth, REN 21 asked 114 energy experts from around the world if they thought we could get to ‘100% renewables’ globally by around 2050. Most (two thirds) said yes, although Indian and Japanese experts were less convinced – it would be hard.

However, a new report from the Energy Transitions Commission, which brings together power and industrial companies, alongside investors, green NGOs and researchers, from both developing and developed countries, says we should head out that way and suggests that, given the right support , ‘it will be possible within 15 years to build power systems that rely on variable renewables for 80/90% of power supply and that can deliver electricity at an all-in cost (including back-up and flexibility needs) of less than $70 per MWh, which is likely to be competitive with fossil fuels based power generation’. It will, they say, be harder in other sectors, with CCS being needed, but they claim that it should be possible to limit global warming to well below 2˚C while stimulating economic development and social progress.

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