Phasing out fossil fuels for renewables may not be a straightforward swap
According to studies, energy supply systems that are 100% renewable are economically and technically achievable, supporting those who believe that fossil fuels can be replaced without much of
Energy of the future
Normally people look at whether or not future energy sources can meet future demand to determine how to reach using 100% renewable energy. This is also known as energy balance. This is a good start, but one thing this type of research can’t do is see what could happen to the total energy supply while the transition from fossil fuels to renewable energy is occurring. A sudden and big-scale transition results in high demand for energy services, which would then result in competition with other economic activities. The reason this high demand exists in the first place could be because there would be a sharp decrease in energy service availability. All these possibilities combined are some of consequences on the economy during transitioning.
What are net energy services?
“Net energy services are the total work and heat that energy sources – for instance solar photovoltaic (PV) systems or petroleum – make available to end users, minus the energy services required to provide that supply.” Looking at net energy services on a global scale helps to predict energy availability during transition. “Petroleum requires energy services to find, produce, transport and refine it. Solar PV systems require energy services for mining raw materials, manufacturing, installation, replacement and so on. The net services are what remains available for all other purposes, such as heating buildings and moving goods and people.”
Predictions have been made that over the course of 50 years, fossil fuels will stop being used, and biomass, hydro, and nuclear energy sources will take about double the time.
The model then attempts to maintain the net energy services to the global economy at the maximum level before the fossil fuel phase-out. To do this it uses electricity from onshore wind turbines and large-scale solar PV plants, buffered with lithium ion batteries.
The findings show that the faster the transition rate, the greater the energy services required by the transition task, and the lower the services available for other uses
If less energy services are available, then energy transition will come at the expense of other economic activity. That may impact the collective will to continue
This is because of the time lag between energy investments and returns. It is exacerbated for sources where up-front energy investment is a relatively high proportion of the total life cycle, particularly so for solar PV.
A 50-year fossil-fuel phase-out represents a relatively modest transition rate. Even so, in the model’s baseline scenario, net energy services decline during that transition period by more than 15% before recovering.
And that recovery is not certain. The model doesn’t consider how this decline in energy services might affect the transition effort. If less energy services are available, then energy transition will come at the expense of other economic activity. That may impact the collective will to continue.
In the model’s baseline scenario – phasing out fossil fuels over 50 years – wind and solar plants need to be installed at eight to ten times current rates by 2035.
Financially, this corresponds with capital investment in wind and solar PV plants plus batteries of around US$3 trillion per year (in 2015 dollars) and average lifetime capital cost in the order of US$5 trillion to US$6 trillion per year.
For comparison, in 2014 the International Energy Agency forecast global investment for all energy supply in 2035 at US$2 trillion per year.
This implies that total expenditure on energy supply will increase its share of world spending, reducing scope for other expenditure. Compounding the decline in energy services during transition, this has potential to apply contractionary pressure to the global economy. This has implications in turn for financing and maintaining the political will for the renewables rollout.
What if it were possible to roll out renewables even faster? This could reduce the depth and duration of the decline, but not eliminate it. Again, due to the time lags involved, accelerating deployment in the short term takes energy services away, rather than adding them.
What does this mean?
Of course, this is “just” modelling. But good models can tell us a lot about the real world. If this modelling is right, and energy services fall and costs rise, we’ll have to complement building cleaner energy supply with other approaches.
The other key aspect of transition that we have control over is how much energy we expect to use. Usually discussions of transition focus on maintaining energy supply sufficient for a growing economy much like we see today – just with “clean” energy. But this is changing.
This is about more than efficiency. It is about a shift in our collective priorities and how we define progress, wellbeing and quality of living
Growing numbers of analysts, business leaders and other prominent figures are calling for broader cultural change, as it becomes clearer that technological change alone is not enough to avoid climate catastrophe and myriad other consequences of energy-intensive consumer societies.
This is about more than efficiency. It is about a shift in our collective priorities and how we define progress, wellbeing and quality of living. Reducing energy demand within these redefined aspirations will markedly improve our prospects for successful transition.