Views differ on renewable energy futures.

As ever, BP’s annual Energy Outlook has renewable energy making only a small primary energy contribution – around 4 billion tonnes of oil equivalent by 2040, i.e. 15% or, including hydro, 22% combined. Non-hydro new renewables do grow rapidly in its scenario, faster than anything else, and coal and oil take a big dive, but gas remains king. Nuclear stays low. But even in BP’s rapid transitions scenario, by 2040 renewables still only hit 29% of global energy (38% with hydro).

To put all this in perspective, IRENA, the International Renewable Energy Agency, looks to renewables supplying around 60% of total primary global energy by 2050. BP’s projections look a bit better in power terms — nearly 30% excluding hydro by 2040 (maybe 46% with hydro), but they’re still well behind the electricity projections from IRENA (85%) and even the IEA (around 70%), especially since electricity demand fell in 18 out of 30 IEA member countries over the period 2010-2017. Obviously, as the IEA keeps saying, we will also need heat and power, as well as a lot of energy saving, but IRENA says renewables, along with efficiency, can help us make 90% of the emission cuts needed to keep below 2 °C by 2050.

That’s very different from the gloomy scenario painted in Jeremy Grantham’s grim GMO white paper: renewables will boom, but not fast enough to avert climate change. BP says basically the same. They do look at scenarios with more of a push on carbon dioxide reduction and with less globalization. But the main message in both studies is that, in all cases, though renewables boom and dominate, fossil fuel will still be large. And so BP’s central scenario expects carbon emissions to grow 10% by 2040, as world energy demand grows by a third and fossil fuels continue to play a key role.

Views clearly differ. IRENA’s recent publication A New World – The Geopolitics of the Energy Transformation is very optimistic, with IRENA’s director general saying that a transition from fossil fuels is “a move away from the politics of scarcity and conflict to abundance and peace with new opportunities for many countries”. Certainly, the geographic concentration of fossil fuels in just a few countries has had a significant impact on the wealth and security of many of them. An energy transformation driven by renewables could bring changes just as radical in scope and impact with a democratization of energy. However, that transition won’t be automatic — there may also be conflicts over access to renewable resources, since they too are not distributed equally around the world.

LUT goes bold

That’s the starting point for yet another new 100% renewables study from researchers at LUT University in Finland and Brazil’s University of São Paulo. “Each regional energy transition will proceed rather uniquely,” says the study. “Each country will have a specific optimal electricity supply mix, but solar PV [photovoltaics] will become the dominating source of electricity globally. Beyond 2040, PV will generate more than half of global electricity demand, and almost 70% in 2050. The 2020s will be most challenging due to the substitution of very high capacities of newly retired fossil fuel and nuclear capacities, and high capex. The transition will require a capex of around 22.5 trillion € (uncertainty range 19–25.5 trillion €), which is comparable to current power sector-related investments.”

Overall the research says: “A sustainable and carbon neutral electricity system based on 100% RE [renewable energy] is technically feasible and economically viable globally by 2050 due to the reasonable total system LCOE [levelized cost of energy] (26–72 €/MWh) with a global average of 52 €/MWh (uncertainty range 45–58 €/MWh).” And it concludes: “For decades the RE share has grown slightly. However, despite discussions about defossilization and decarbonization of the energy system, GHG [greenhouse gas] emissions keep on growing. In order to fulfill the Paris Agreement requirements as well as the United Nation’s Sustainable Development Goals, a greatly accelerated transition should be started soon.”

It’s a bold study: 22 TW of PV will generate nearly 70% of all electricity, and 3.2 TW of wind nearly 18%. Enough to save the day, with hopefully plenty spare for heat and transport – if LUT proves to be right. And if the costs are as low as the researchers expect. That is certainly claimed to be likely; in yet another challenging report, LUT and its research partner the Berlin-based Energy Watch Group (EWG) insist that 100% renewable EU scenarios will be more cost-effective than the current system. More on that in my next post

Other views

Not everyone agrees. New modelling by Dutch researchers of seven scenarios for the European power system in 2050, based on 100% renewable energy sources, did find that “a 100% renewable European power system could operate with the same level of system adequacy as today when relying on European resources alone, even in the most challenging weather year observed in the period from 1979 to 2015”. However, they also said that realizing such a system by 2050 would be expensive: “Even when wind and solar photovoltaic capacity is installed in optimum locations, the total cost of a 100% renewable power system (∼€530 bn p.a.) would be approximately 30% higher than a power system which includes other low-carbon technologies such as nuclear, or carbon capture and storage (∼€410 bn p.a.).” That echoes the conclusion of a global study from Harvard University, US; 100% scenarios could be viable, but they might cost more than other approaches.

If you blinked, you missed it. An obscure energy company based in Denver has just figured out how to provide rural electricity ratepayers with what they desire: renewable energy at low prices that beat the stuffing out of ancient coal power plants. If all goes according to plan, the maneuver could lay the groundwork for retiring both coal and gas power plants at a more rapid clip.

The relatively high costs of 100% renewables scenarios predicted in some studies could be reduced if demand could be cut more. The costs could fall further if reliance on relatively high-cost biomass sources was reduced, as could be the case if Power to Gas (P2G) conversion of surplus renewables output was used. The Dutch study does not look at that. LUT did and was also quite sparing in its use of biogas — it mostly used P2G instead for balancing, along with other storage options. That would no doubt be welcomed by Jacobson et al. at Stanford University, US, and elsewhere. In their 100% renewable global 2050 scenario, they avoid all use of biomass (landfill gas apart), and reckon their wind, water and solar mix will cost less than current approaches, even with balancing/storage costs added.

Given that renewable costs continue to fall, while nuclear costs are still rising and high-cost carbon capture and storage (CCS) — though not carbon capture and utilization (CCU) — is sliding out of policy focus, that view seems increasingly credible. And that ignores the likely high social and economic cost of continuing to use fossil fuels. In my next post I look in more detail at the latest 100% renewables scenarios – the LUT/EWG all renewable energy global study and an update of Jacobson’s all renewable energy study. They go way beyond the more conventional scenarios – from Shell, Statoil, Exxon, IEA, IPCC and others – reviewed recently by the World Energy Council, most of which, like BP’s scenario above, still have fossil fuels playing significant roles. Take your pick.

29 May 2019

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