Beyond Efficiency and Renewable: Sufficiency Matters to Limit Global Warming by the End of the Century to 1.5°C

This entry to the blog was written by Dr. Yamina Saheb, climate mitigation scientist and WiRe Fellow whose work and research focuses on designing sustainable policies to ensure wellbeing for all within planetary boundaries.

This blogpost is a slightly altered version of the sufficiency section included in the report entitled 1.5-Degree Lifestyles: Towards a Fair Consumption Space for All published by Hot or Cool Institute. Dr. Saheb’s contribution to this report introduces and examines sufficiency practices, which are long-term actions and societal changes driven by non-technological solutions. Sufficiency (in contrast to the want-based efficiency approach to climate policy) focuses on human needs and services required for wellbeing (i.e., housing including thermal comfort, nutrition, mobility…).

Global warming is today’s reality in every region of the planet

Heatwaves, heavy precipitation, agricultural and ecological droughts in some regions, tropical cyclones, as well as reductions in Arctic Sea ice, snow cover and permafrost are unfortunately what 2021 will be remembered for. Changes of the global climate system became indisputable. Extreme weather and climate events driven by human-induced warming of the atmosphere, ocean and land is unequivocal (Masson-Delmotte 2021).  Every region across the planet has experienced in 2021 at least one climate and weather extreme event. The global climate system has changed because of the global warming caused by the continuous increase of greenhouse gas emissions driven by human activities. Carbon dioxide emissions, resulting from the use of fossil fuels, is the main greenhouse gas contributing to global warming. Over the period 1750-2019, global carbon dioxide concentration increased by 48% to 410 ppm (parts per million) (Global Carbon Budget 2021) leading to an increase of global surface temperature of 1.09°C compared to the pre-industrial temperature levels (Masson-Delmotte 2021).

Three decades of climate mitigation action failed in limiting global warming

Scientifically informed warnings about the potential catastrophic impacts of human-induced global warming were already included in the first Intergovernmental Panel on Climate Change (IPCC) report published in 1990. Political efforts have since triggered international collaborations to limit greenhouse gas emissions. The United Nations Framework Convention on Climate Change (UNFCCC), adopted in 1992, was the first step towards limiting global warming. The Kyoto protocol, which introduced the first-ever greenhouse gas emissions reduction targets, was adopted in 1997 with the aim to strengthen the UNFCCC. More recently, the Paris Agreement adopted in 2015 introduced the objective of holding the increase of global average temperature by the end of the century to well below 2°C above pre-industrial levels, while pursing efforts to limit the temperature increase to 1.5°C above pre-industrial levels.

These international agreements were all followed by countless action plans which included several policies and strategies to reduce greenhouse gas emissions. Yet, global carbon dioxide emissions from fossil fuels continued to increase during the last three decades and reached 36.4 Giga tonnes in 2019, which is 61% more than in 1990 (Global Carbon Budget 2021) (Figure 1). The only decrease of emissions observed was in 2020 due to the health crisis. However, given the lack of structural changes, this decrease is likely to be offset in 2021.

Policymakers, scientists, and business leaders must admit that the current approach to climate change mitigation, which is driven by technological breakthrough, behaviour change of individuals and market-based instruments failed in limiting the effects of global warming. Importantly, limiting global warming to 1.5°C above pre-industrial levels by the end of the century, as called for by the landmark Paris agreement, will be out of reach without a metamorphosis of the existing climate mitigation policy framework.

Figure 1:

Sufficiency: the overlooked climate mitigation strategy

Sufficiency is about living within planetary boundaries. It is defined as a set of policy measures and daily practices which avoid the demand for energy, materials, land, water and other natural resources, while delivering a decent living standard for all within planetary boundaries (Saheb 2021). Decent living standards entail a set of essential material preconditions for human wellbeing which includes housing, nutrition, basic amenities, health care, transportation, information, education and public space (Rao, Min, and Mastrucci 2019); (Rao and Baer 2012); (Rao and Min 2018).

Sufficiency was introduced to the sustainability policy debate by Sachs (1993b) and to academia by Princen (2003a). With the adoption of the Paris Agreement (United Nations 2015) and the collective failure in curving global greenhouse gas emissions after three decades of climate mitigation policies (Stoddard, 2021) (Figure 1), sufficiency is emerging as a climate mitigation strategy to compensate for the unsuccessful efforts of efficiency and the supply with renewable energy sources in reducing greenhouse gas emissions (Saheb 2021).  

Sufficiency is often conceptualised by contrast to efficiency. The latter is about the continuous short-term marginal technological improvements which allow doing more with less in relative terms without considering planetary boundaries, while the former is about long-term actions driven by non-technological solutions (i.e. land use management), which consume less in absolute-term and are determined by the biophysical processes (Princen 2003b). The focus of sufficiency is on human needs and the services required for human wellbeing (i.e., housing including thermal comfort, nutrition, mobility…) while the focus of efficiency is on human wants such as products and commodities (buildings, cars, appliances, energy). In that sense, efficiency is a supply-side strategy while sufficiency is a demand-side one.

Sufficiency questions the current approaches to climate change mitigation, such as the promise of technological breakthrough prioritised over lifestyle changes, behavioural change of individuals over systemic change of the economy and the organisation of the society, the cost-benefit analysis emphasised over the biophysical reality of the planet and the market-based instruments over redistributive ones. Moreover, sufficiency confronts the dominant individually-focused discourse which puts emphasis on trivial actions such as turning lights off when rooms are empty, and uses over-reliance on the technological improvements driven by efficiency, which ultimately just substitutes one technology with another. This substituting approach only increases the demand for materials and their related embodied energy and carbon. Unsurprisingly, sufficiency is considered controversial by the wealthiest in society because it challenges their carbon-intensive lifestyles. In fact, sufficiency requires large changes in the consumption patterns and puts an indisputable cap on the consumption levels based on the remaining carbon budget to avoid the overshoot of the 1.5°C temperature target.

The remaining carbon budget and its normative target for distributional equity is the upper limit of sufficiency, while requirements for a decent living standard define the minimum level of sufficiency. By limiting the over and under demand for energy, materials, land, water and other resources, sufficiency is likely to become, in the current decade, central to the global climate mitigation strategy (Saheb 2021). The untapped sufficiency potential, which may reach 30% emissions reduction in the wealthiest countries, will contribute to address the unprecedented and urgent transformation of the global economy and to limit the unequivocal role of human activities in global warming.

Sufficiency principles include the moderation of the speed to enjoy life, the reduction of distances between suppliers and consumers to avoid the ecological breakdown, the limitation of trade to focus more on commons as well as the limitation of goods’ ownership (Sachs 1993a). Implementing sufficiency principles requires i) structural changes to moderate the demand for energy, materials, land, water and other resources as well as ii) flexibility to allow for developing usership of services and for adapting the size and the use of goods to the evolving human needs (Negawatt 2003) (Grubler et al. 2018).

Sufficiency practices

As described in the section below, by considering an equal distribution of the remaining carbon budget for the 1.5°C temperature target as an upper limit, sufficiency requires a metamorphosis in the way human needs (i.e., housing, mobility, nutrition) are satisfied. 

1. Housing

The continuous increase of the floor area per-capita experienced in developed countries is a hidden driver of emissions from the building environment at the construction and the operation stage (Lamb et al. 2021) (Röck et al. 2020). Applying sufficiency principles to housing requires putting a cap on the per-capita floor area. This cap could be achieved by downsizing dwellings through co-housing strategies by clustering apartments when existing buildings are renovated and by prioritising multi-family buildings over single-family homes in new developments (Sandberg 2018) (Stephan, Crawford, and de Myttenaere 2013)(Duffy 2009)(Fuller and Crawford 2011)(Wilson and Boehland 2005)(McKinlay, Baldwin, and Stevens 2019)(Sandberg 2018). The cap on the per-capita floor area will reduce the land take and have a direct impact in reducing the demand for materials, water and other natural resources  in the construction phase and energy demand for heating, cooling and lighting in the use phase (Duffy 2009) (Heinonen and Junnila 2014) (Saheb 2021). Less space also means fewer appliances and equipment, or changing preferences towards smaller ones (Aro 2020).

Cohousing strategies provide users, in both new and existing buildings, a shared space (i.e, for laundry, offices, guest rooms and dining rooms) to complement their private space, thus reducing per-capita consumption of resources including energy, water and electricity (Klocker, Gibson, and Borger 2012)(Natascha Klocker 2017), while offering social benefits such as limiting loneliness of elderly people and single parents (Riedy et al. 2019)(Wankiewicz 2015). Senior cooperative housing communities and eco-villages are considered primary cohousing examples, ideal to scale-up (Kuhnhenn et al. 2020).

Local authorities have an important role to play in the metamorphosis of housing by proposing communal spaces to be shared (J. Williams 2008)(Marckmann, Gram-Hanssen, and Christensen 2012) through urban planning and land use policies (Duffy 2009)(Newton, Meyer, and Glackin 2017). The role of local authority is vital in encouraging inter-generational cohousing as well as interactions between people with different backgrounds (Lietaert 2010)(J. Williams 2008). Progressive property taxes based on a cap in the per-capita floor area are also needed to trigger the adaptability of the size of dwellings to households’ needs (Murphy 2015).

2. Mobility

Over the last three decades of climate mitigation policies, emissions from mobility have increased in all countries (Lamb et al. 2021), driven by the expansion of the use of private cars due to urban sprawl, the lack of public transport as well as the social and financial incentives to become a car owner. Sufficiency practices to reduce emissions from mobility include living car-free, ride sharing, reducing the travelled-distances, the weight of private cars and imposed speed limit (Bigo 2020). However, the focus of policies and research has been mainly on changing the behaviour of individuals through car sharing instead of ride sharing (Shaheen, Mallery, and Kingsley 2012)(Chen and Kockelman 2016) and on making mobility smarter (Arnott et al. 2014) (Marsden et al. 2014) (Barr 2018) (Moriarty and Honnery 2012). The contribution of structural changes to reducing emissions from mobility through new cycling and walking infrastructure, ride sharing and friendly public transport (Hasselqvist and Hesselgren 2019) (Dijk et al. 2019) are rather neglected in both policies and research.

Air travel and related emissions have also increased in the last three decades  (Gössling and Humpe 2020), especially with the increased offers for low-cost flights and leisure as well as the variety of frequent flyers’ benefits. More recently, there has been an increased focus on avoiding air travel due to the flying shame movement. Avoiding air travel by using other modes of transportation and slowing travel to re-discover enjoyment of the journey are among the sufficiency practices identified in the literature (Morten, Gatersleben, and Jessop 2018)(Jacobson et al. 2020)(Dickinson, Lumsdon, and Robbins 2011) to reduce emissions from air travel, which are estimated at 1.6 tCO2e per capita saved per roundtrip transatlantic flight (Wynes and Nicholas 2017).

Applying sufficiency principles to mobility requires framing mobility as a service to be provided within the limited per-capita carbon budget to avoid the overshoot of the 1.5°C temperature target. Urban planning and land use policies (Duffy 2009)(Newton et al. 2017) play a major role in triggering or avoiding the daily travelled distances. High density, multi-functional areas, teleworking as well as progressive taxation of frequent flyers and owners of multiple cars and private jets and the ban of SUVs are among the sufficiency solutions to limit emissions from mobility.

3. Nutrition

Meat consumption and dairy products are the two major contributors to greenhouse gas (GHG) emissions identified in the literature (Institute for Global Environmental Strategies, Aalto University, and D-mat ltd 2019) (Willett et al. 2019)(Hedenus, Wirsenius, and Johansson 2014). Dietary changes will have a significant impact on limiting the overshoot of the 1.5°C target, especially in countries with affluent food. Avoiding all animal-based products in developed countries would reduce food related emissions by more than 50% (Hallström, Carlsson-Kanyama, and Börjesson 2015). However, the focus of policies has been more on organic food than on less-carbon intensive one.

A changing and innovative food perspective, which includes prolonging the lifespan of food through a better planning, purchasing, storing, cooking and managing the leftovers is also among the strategies highlighted in the literature to reduce food waste and losses, and consequently their related emissions (Roodhuyzen et al. 2017)(Schanes, Dobernig, and Gözet 2018) (Willett et al. 2019). At a global level, about one-third of the food produced for human consumption is lost or wasted. This is equivalent to 1.3 billion tons per year. The highest food lost or wasted is observed in developed countries with an annual of 95-115 kg/capita, in comparison to 6-11 kg/capita in developing countries (Gustavsson, J., Cederberg, C., Sonesson, U., van Otterdijk, R., & Meybeck 2011).

4. Other goods and services

Sufficiency strategies suggested in the literature for products and goods are similar to those related to nutrition (Freudenreich and Schaltegger 2020). Increasing the lifespan of products and goods by penalising corporately-planned obsolescence as well as moving away from a linear use of materials and products to a circular one by reducing, reusing, recycling, and producing locally will reduce emissions created from the production of goods. Moving from ownership of products to usership of services (Negawatt 2003)(Grubler et al. 2018) as well as a slowing down their use (i.e. Slow fashion) (Joyner Armstrong et al. 2016) are also among the sufficiency practices to consider.

Into the future

Global warming is, unfortunately, expected to continue and its impacts will have consequences for everyone, but those living in the poorest countries will be the most affected. Drastic emissions reduction must occur in the 2020-2030 decade to limit the overshoot of the 1.5°C temperature target during the 21st century (Masson-Delmotte 2021). Addressing the climate emergency requires moving on from the current framework driven by efficiency improvement and the decarbonisation of energy supply through renewable energy sources to a framework based rather on a combination of sufficiency, efficiency and renewable (SER) (Figure 2). Such a framework is needed to deliver on the Paris Agreement’s temperature and equity objectives.

Figure 2: Sufficiency, Efficiency, Renewable (SER) climate mitigation framework

© Saheb.Y, Beyond efficiency, sufficiency matters. Energy and Buildings Journal, 2021

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