Powering a Sustainable and Circular Economy—An Engineering Approach to Estimating Renewable Energy Potentials within Earth System Boundaries

Abstract

This study proposes a method to estimate the appropriability of renewable energy resources at the global scale, when Earth system boundaries/needs and the human demand for chemical energy are respected. The method is based on an engineering approach, i.e., uncertainties of parameters and models are considered and potentials calculated with 99% confidence. We used literature data to test our method and provide initial results for global appropriable technical potentials (ATP) that sum up to 71 TW, which is significantly larger than the current global energy demand. Consequently, there is sufficient renewable energy potentially available to increase energy access for a growing world population as well as for a development towards increasingly closed material cycles within the technosphere. Solar energy collected on the built environment (29%) and in desert areas (69%) represent the dominant part of this potential, followed in great distance by hydro (0.6%), terrestrial heat (0.4%), wind (0.35%), and biomass (0.2%). Furthermore, we propose indicators to evaluate an energy mix on different levels, from an energy mix in single products to the mix used by the global economy, against the estimated RE potentials, which allow an evaluation and consideration in the design of sustainable-circular products and systems.Energies 2019, 12, 4723 2 of 18 drivers for global environmental disruption [7], for example triggering a climate crisis [8][9][10][11]. Nuclear energy harvested in today's fission reactor fleet, though contributing little to the climate crisis, rapidly depletes the uranium stock, poses catastrophic risks for human and ecosystem health in case of accidents, increases the possibility for development and proliferation of nuclear weapons, and leaves radioactive waste to be managed for millennia by future generations [12]. Both fossil and nuclear energy resources are therefore incompatible with the notion of sustainable development, since it is defined as a "development that meets the needs of the present without compromising the ability of future generations to meet their own needs" [13]. Consequently, a sustainable CE can only be powered by RE fluxes in the future.The Earth system is powered by three incoming RE fluxes: solar irradiance, terrestrial heat, and tides. The latter two contribute very little to the Earth's energy budget, i.e., 0.03% and 0.002%, respectively [14][15][16][17]. Solar irradiance is therefore the pivotal power source for the circulation of natural and anthropogenic materials in an otherwise closed Earth system. The Earth system balances these energy inflows mainly with infrared emittance, which is adjusted by the Earth's surface temperature [18]. All material cycles within the Earth system, be they natural or anthropogenic, are enabled by these energy fluxes, which are approximately five orders of magnitude larger than the current human demand for technical energy (i.e., energy used to power technical processes, such as electric energy) [6]. Throughout the Earth's history, these energy flu...

Carbon budgets for buildings: harmonising temporal, spatial and sectoral dimensions

“…from fossil to renewable energy) may reduce GHG emissions, but increase the pressure on other environmental issues. For renewable energy, the pressure increases particularly on biodiversity, land and water (Desing et al 2019). Specific resources might become critical for a transition towards low carbon economy (de Koning et al 2018;Nansai et al 2014).…”

Ecological resource availability: a method to estimate resource budgets for a sustainable economy

“…The ERA method is based on the precautionary principle, which means that despite the often large uncertainties in both boundary values and impact measurements, the resulting ERA budgets needs to be viable with high confidence (Desing et al , 2019, 2020). Therefore, an acceptable probability of violating the defined boundaries P v is required as an input parameter.…”

“…The adaptation of the boundaries is based on the literature and for the purpose of demonstrating the ERA method. Furthermore, the probability of violating the boundaries is set to P v = 0.01 (Desing et al , 2019) to illustrate the method. This is in between the probability of failure tolerated for critical technical systems (usually <0.001; see Table S2) and deemed acceptable in current Earth system governance (e.g., P v = 0.33 for reaching the 2.0°C target (IPCC, 2013); P v = 0.5 for reaching the 1.5°C target (IPCC, 2018), despite potentially catastrophic effects (Lenton et al , 2019)).…”

“…The PB framework can be refined with more detailed control variable definitions (e.g., for biodiversity, see Alig et al , 2019; Mace et al , 2014) or extended to other variables (e.g., net primary production O'Neill et al , 2018; Running, 2012). To show this, we add a boundary on renewable energy potentials (Desing et al , 2019), representing the amount of energy that can be appropriated by society without transgressing other critical PBs (e.g., land-system change) or compromising food supply. The global appropriable technical potential (ATP) for renewable energy is estimated to be (Desing et al , 2019).…”

Energy Use and Climate Change: History and Foresight

“…Instead, future prospects of theoretically possible renewable energy provision from the different renewable energy technologies in absolute values (without accounting for land or material competition) gives a first rudimentary insight in the possibility to change the global energy system to a renewable one. For a more detailed analysis of a systemic analysis of maximum renewable energy potentials on a worldwide level, the reader is referred to Desing et al (2019).…”