Living within Planetary Limits — a Piece of Cake?

Peter Wurmsdobler
9 min readOct 10, 2023


Planet Earth offers finite resources and has therefore a limited carrying capacity for all its inhabitants. Since our global, industrialised civilisation got into the habit of exceeding its carrying capacity, consequences such as climate change or ocean acidification will eventually undermine its foundations. The response is quite varied. Some think that our civilisation can continue with business as usual, simply by throwing enough technology at the issues. Others are convinced that the established economic system has to be overthrown. And still others see in de-growth the answer to all worries. How can we live within planetary limits?

Tarte aux abricots (Maison Clement) with cake fork (courtesy of Cambs Antique Centre)

In Western society, cake — or at least most types of cakes — are traditionally eaten with a three-pronged cake fork which has one wider tine that can be used for cutting through pastry. In the same vein I would claim that living within planetary limits requires a three-pronged approach: a combination of technology, economics & society; they are not mutually exclusive but complementary. Similarly to the cake fork, one factor is employed to cut a bit deeper, societal changes.

Before looking into the three prongs in more detail, let’s consider the quantification of human impact on the environment using the so-called I-PAT model: the impact I is a product of the three factors population (P), affluence (A) and technology (T), or I = P · A · T.

Technology and Efficiency

Based on the I-PAT model, for a given population and desired level of affluence, the impact on the environment can only be lowered by decreasing resource intensity (T), i.e. increasing resource efficiency. Extending Michael Barnard’s Commandments of Climate Change:

  • Electrify Everything. Energy is required for all transformations in general, and human activities in particular: agriculture, transport, manufacturing as well as residential, commercial and industrial heat; currently these processes are mostly powered by fossil fuels. Their electrification will address an inherent inefficiency of fossil fuel usage: the limits of the thermodynamic efficiency of about 20–50% (30% on average) when converting chemical energy through combustion into useful energy, mechanical or electrical (see Energy Flowchart). As Michael says: We only have to replace a third of the actual primary energy we use today to maintain our lifestyle and economy.
  • Overbuild Renewable Energy Generation. The sun is the only independent energy source with an influx of about 174,000 TW at the edge of the atmosphere yielding about 83,000 TW at the Earth’s surface. The learning curve in the production of solar panels resulted in very inexpensive production of solar energy to an extent that it has become the cheapest form of energy production. It has even become affordable to simply overbuild capacity to compensate intermittency to some extent; this is true for wind generation, too. Excess power can be used to produce green hydrogen for industrial processes which is ideally located closely to the energy production sites.
  • Continent-Scale Electrical Grids. Distribute energy supply and demand on a large grid which has an obvious equalising effect. When power is needed in one location, the sun may shine or the wind may blow in another location. Development of large grids, super grids and a global grid, using UHVDC interconnects is a way to exchange power in international electricity markets: east-west for daily changes, and north-south for seasonal changes. There might be political issues, but I do hope that in the face of Climate change’s consequences, political obstacles can and have to be overcome.
  • Demand Response. The objective of demand response is to adjust the demand to follow supply; in a more classical approach supply follows demand. A desirable demand response can be achieved by introducing spot-pricing for energy with a forecast of energy prices for a horizon ahead, e.g. flexible energy prices, i.e. a feedback-loop to the consumer.
  • Pumped Hydro And Other Storage. Energy storage is a buffer between supply and demand; store energy into the buffer when there is more supply than demand, retrieve energy from the buffer in the opposite case, both seasonally and daily: technically, a low pass filter that removes spikes. Storage can be distributed, be at domestic and utility scale, using a combination of battery, pumped hydro and other means.
  • Regenerative Agriculture and Trees. A new way of farming systems needs to be established: knowledge based farming and Regenerative Agriculture, with large scale “no-till” and/or “reduced till” practices as portrayed in the documentary Kiss The Ground as well as smart & precision farming and agro-forestry, i.e. more trees. This approach is capable of sequestering large amounts of carbon dioxide into the soil while maintaining its health and feeding the world.
  • Concrete, Steel And Industrial Processes. Current cement production emits CO2 in two ways: combustion of fossil fuel for heat and CO2 released from heating chalk. Electrification of the former and capture of CO2 of the latter is needed. As for steel, the more our civilisation moves towards a stationary process, the more steel is recycled, which can be electrified (and partly already is). The additional new steel can be made employing electro-reduction by using overbuilt electricity generation, possibly collocated with solar plants.
  • Shared Mobility. Personal mobility has to be addressed foremost though urban planning (allowing the avoidance of locomotion), and failing that, through multi-modal transport solutions, including walking, cycling and most importantly shared forms of transport; public means of transport such as trains and electric buses should play a greater role. In short, fewer miles travelled is the answer as well as fewer individually owned cars. The total number of vehicles to meet mobility needs should become a fraction of the number of cars today.

Note that these actions open up business opportunities for different industries while some incumbents would need to shrink; so it is a transfer of activities and shift of focus. While all these actions will help towards the goal of Living within Planetary Limits, they are necessary but not sufficient.

Economics and Externalities

Several traits characterise the established economic system: private capital ownership, pursuit of profits by all economic agents, free markets deliver optimal results. I am by no means an economist, but a control systems engineer with a strong interest in economics. As such, I believe that optimal control is a combination of feed-forward and feed-back control: use all information to plan actions, a-priori (from first principles) and a-posteriori (observed & measured).

Another premise: there seems to be an innate human trait to optimise for oneself by pursuing one’s own interest. This part of Adam Smith’s work is often used and usurped to claim that unconstrained pursuit of profit alone in a free market will yield optimal results. The other, less known part of Smith’s work emphasises that “institutional conditions have to be fulfilled such that they force self-interest to work in the interest of the common good; it is the task of statesmen to create institutions and laws that forces even bad people to act in the interest of the common good.” The latter constitutes for me an overall outer feedback loop that sets the conditions and constraints for economic agents to go after their business (inner feedback loops).

On economic constraints: Arthur Cecil Pigou is perhaps most known for his work on negative and positive external effects, leading to a model for optimal taxation that will enforce internalising of known negative economic externalities. Taxation is perhaps one means to set up economic constraints; these constraints would nowadays be based on both a-priori (first principles) models as well as a-posteriori (data science) models and are continuously adjusted as we learn about effects of economic activity, such as carbon emissions. I would go as far as introducing a Gaia Tax — A Compensation for Extracting Earth’s Resources.

That said, known side effects of fossil fuels have to be quantified and added as financial constraints; markets will adjust accordingly. Consequently, energy and resource intensive habits will become uneconomic. In the same vein, subsidies for economic activity that is found to be damaging has to be curtailed and eventually be stopped (Trillions In G20 Fossil Fuel Subsidies Fuel Profits And Climate Change).

At a wider scope, I would like to quote a few factors Tim Jackson lists in his Prosperity Without Growth, without going into further detail:

  • Enterprise as a services — a transition from producing more and more material products to services around a smaller number of those, i.e. re-use, refurbish and share: platforms for sharing stuff built for longevity. For example, consider reading shared books as opposed to owning books as long as the quality of service allows to meet the need.
  • Work as participationwork offers respect, motivation, fulfilment, involvement in community and a sense of meaning and
    purpose in life.
    This is related to Peter Victor’s study for the Canadian economy: maintain the economic output with a reduction of working hours, rather than compensating increased productivity with more consumption.
  • Investment as commitment — Investment embodies one of the most vital relationships in economics — namely the relationship between
    the present and the future. Rather than investment directed at the extraction of rents from finite material resources, …, invest in material efficiency, carbon footprint of the utilities sector, … , channelling of investment funds towards ethical, social and sustainable companies.
  • Money as social good Most money circulating in advanced economies is created by commercial banks. Banks create money by making loans. …. There is a call for an end to bank’s power to create money and the implementation of a so-called ‘sovereign money’.

Note that all these factors are not “anti-business”, but merely a paradigm shift in economic activity, a pivot from one kind of business to another. Still, while all additional these actions will help towards the goal of Living within Planetary Limits, they are necessary but still not sufficient.

Society and Politics

While the previous prongs or tines will make sure that products are made in a resource efficient manner (Technology) and are correctly priced (Economics), the issue of the underlying economic growth conundrum still remains: in order to stay within planetary boundaries, economic growth will have to converge to zero due to the need of a material basis; this is a contradiction to the economic growth imperative of our civilisation. Something more fundamental will have to change, a change in the value system of society; this is why a stronger tine is needed that cuts through a tough cake. An economy, our civilisation for that matter, can only be truly sustainable if it can continue indefinitely within the planet’s regeneration capacity. And sorry, mining minerals is off the menu as mined resources are per definition not renewable.

It is perhaps worth noting that the alternative to the economic growth imperative does not necessarily mean “going back to subsistence farming” or austerity as often used to stifle questioning of the growth paradigm. The industrial revolution and subsequent social changes have lifted a lot of people out of poverty allowing an increasing number of people a decent living standard which was only afforded to few, and continues to do so. According to the late Hans Rosling, poverty could be eradicated within 15 years. However, there is one important factor that goes beyond producing the necessary material substrate for prosperity: consumerism.

The underlying problem I see here is that gains in labour productivity result in the need for fewer hours worked given a constant population and constant production. John Maynard Keynes already predicted that people will need to work fewer hours in a few decades in order to produce all major commodities. This would have required sharing those gains between all stakeholders. Instead, shareholders ask for a return on their investment as profits increase because fewer people are needed who work the same amount of time. The superfluous workforce needs to work in new factories to produce new things to keep the economy going; consumption has to be stimulated. In summary, the labour productivity gain has to be compensated with the introduction of more products in order expand demand.

Kerryn Higgs’ article A Brief History of Consumer Culture points out that in the 1920s “the fear that the immense productive powers created over the previous century had grown sufficiently to meet the basic needs of the entire population and had probably triggered a permanent crisis of overproduction”. Sigmund Freud’s nephew Edward Bernays was instrumental in employing psychology and propaganda to the spread the “`new economic gospel of consumption`, in which workers could be educated in the new `skills of consumption`.” A few decades later, in 1955, Victor Lebow proclaimed “that we convert the buying and use of goods into rituals, that we seek our spiritual satisfaction, our ego satisfaction, in consumption.” Now, this consumer culture is firmly entrenched in our society, fuelled by a desire for novelty and social status (for example SUVs?).

It will need a profound societal change to revert consumerism and transition to a less materially oriented but human-centred society that values education, science, art and care; the economy serves humans and not the other way round, or paraphrasing David MacKay, less stuff with its life cycle of goods -> clutter -> rubbish. It is a difficult political task to promote, but I think it will be necessary and perhaps sufficient. A starting point would be the limiting of advertising and advertising based business models that stimulate consumption.

May I finish with John Stuart Mill: “The best state for human nature is that which, while no one is poor, no one desires to be richer, nor has any reasons to fear being thrust back, by the efforts of others to push themselves forward.”



Peter Wurmsdobler

Works on the technological foundations of autonomous vehicles at Five, UK. Interested in sustainable mobility, renewable energy and regenerative agriculture.