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Population: One Planet, Too Many People?

By 2100, experts predict the global human population to reach about 9.5 billion. Meeting the needs and demands of these people will provide a significant challenge to governments and society at large. The Institution’s latest report: Population: One Planet, Too Many People? looks at how engineers can address the issues of food, water and energy supply for an ever urbanised population over the next few decades.

By 2100, experts predict the global human population to reach about 9.5 billion.  Meeting the needs and demands of these people will provide a significant challenge to governments and society at large.  The Institution’s latest report: Population: One Planet, Too Many People? looks at how engineers can address the issues of food, water and energy supply for an ever urbanised population over the next few decades.

The lead author on the report was the Institution’s Head of Energy, Environment and Climate Change, Dr Tim Fox FIMechE, who wrote the report after consultations with 28 engineers, including members, around the world.

The report acknowledges that by 2100, the global human population may reach 9.5 billion with 75% of these people located within urban settlements.  Meeting the needs and demands of these people will provide significant challenges to governments and society at large, and the engineering profession in particular.

Four key areas in which population growth and expanding affluence will significantly challenge society are: food, water, urbanisation and energy.

Food: An increase in the number of mouths to feed and changes in dietary habits, including the increased consumption of meat, will double demand for agricultural production by 2050. This will place added pressures on already stretched resources coping with the uncertain impacts of climate change on global food production.

Water: Extra pressure will come not only from increased requirements for food production, which uses 70% of water consumed globally, but also from a growth in demand for drinking water and industrial processing as we strive to satisfy consumer aspirations. Worldwide demand for water is projected to rise 30% by 2030, this in a world of shifting rainfall patterns due to global warming-induced climate changes that are difficult to predict.

Urbanisation: With cities in the developing world expanding at an unprecedented rate, adding another three billion urban inhabitants by 2050, solutions are needed to relieve the pressures of overcrowding, sanitation, waste handling and transportation if we are to provide comfortable, resilient and efficient places for all to live and work.

Energy: Increased food production, water processing and urbanisation, combined with economic growth and expanding affluence, will by mid-century more than double the demand on the sourcing and distribution of energy. This at a time when the sector is already under increasing pressure to reduce greenhouse gas emissions (on average across the globe to 50% of 1990 levels), adapt to uncertain future impacts of a changing climate and ensure security of future supply.

The Institution recognises the scale of these issues and that there is a need to begin implementing the early phases of routes to sustainable solutions. The long timescales involved in many of the engineering-based projects required to meet these challenges, often measured in decades of construction and implementation, mean that if action is not taken before a crisis point is reached there will be significant human hardship. Failure to act will place billions of people around the world at risk of hunger, thirst and conflict as capacity tries to catch up with demand.

In meeting these needs and demands, the Institution recommends the following:

  1. The adoption by governments of five Engineering Development Goals alongside the UN Millennium Development Goals. In the key areas of food, water, urbanisation and energy, engineers have the knowledge and skills to help meet the challenges that are projected to arise. There is no need to delay action while waiting for the next great technical discovery or a breakthrough in thinking on population control. In this report we present five Engineering Development Goals for priority action and crisis prevention. Governments around the world must adopt these goals and start working with the engineering profession on delivery targets if we are to build on The Millennium Development Goals.


    Energy: Use existing sustainable energy technologies and reduce energy waste. Don’t wait for new technologies to be developed.

    Water: Replenish groundwater sources, improve storage of excess water and increase energy efficiencies of desalination.

    Food: Reduce food waste and resolve the politics of hunger.

    Urbanisation: Meet the challenge of slums and defending against sea-level rises

    Finance: Empower communities and enable implementation.

  2. Provide all nations and leaders with engineering expertise. Many governments around the world lack high-quality engineering advice and guidance to make informed decisions for implementation of the Engineering Development Goals (recommendation 1). Many developed nations already provide assistance in areas of medical knowledge and primary/secondary education with great success – the UK does via Department for International Development (DFID). The Institution recommends that the remit of DFID be expanded to train and second civil, mechanical, water, agricultural and electrical engineers to provide other governments with low-cost, practical and up-to-date engineering expertise.
  3. Help the developing world to ‘leapfrog’ the resource-hungry dirty phase of industrialisation. The majority of future economic and population growth is projected to occur in the South. However, knowledge of potential sustainable solutions, and experience of the failings from unsustainable dirty industrial activity, are currently concentrated in the North. If economic market forces are left to be the sole or major driver of intervention and action is delayed, then the same errors are likely to be made. Nations in the developed world, such as the UK, must help the developing world to leapfrog the high-emissions resource-hungry phase of early industrialisation to reduce the environmental impact on us all.

Read the full report Population: One Planet, Too Many People?

See an interview with Dr John Bongaarts, one of the contributing authors of the report.

View press coverage of the report.



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8 comments from readers

David Williams

27 January 2011 at 18.45

One partial solution to future food shortages is to reduce current levels of waste. I investigate problems in food storage and have worked in 20 countries. Lack of infrastructure, poor maintenance and management are major factors contributing to the massive wastage of crops, all of which are grown using water, fuel and fertilisers. It takes 1300 litres of water to grow 1kg wheat and 3000 to grow 1Kg rice. India admits to losing 21 million tons of wheat annually equivalent to the entire production of Australia. SE Asia loses 180 million tons of rice annually. The former Soviet Union loses around 25 million tons due to outdated and badly maintained stores and broken trucks. Many African countries lose 50% of their crops. I've recently investigated one loss of 6000 tons of UN Food AID due to lack of understanding of issues by UN Staff. Simple remedies can prevent these losses and increase grain supplies by 250 million tons without growing another grain.

Tim Kirker

27 January 2011 at 21.43

Instead of planning to cope with 9.5 billion people, why is nobody addressing the much easier objective of stopping the human race breeding so prolifically?

Nathan Walker-Powell

28 January 2011 at 9.46

The boom and bust cycle of nature will hit us hard in the near future. If the population continues to skyrocket, then a massive amount of the population will die of starvation as food grows scarce. You see it in nature, im sure any GCSE students reading this will have seen the population scales for rabbit and fox population in biology- the one that looks like two sine waves? As rabbits die out, foxes die out, then rabbit population increases, so fox population increases. The same thing will happen to humans, unless we can mass produce food with GM crops and cloned livestock, and even they need to have some sort of food source.

In all fairness, I cant see a solution to this. The only thing i can think of is to find another earth-like planet and colonise it before 2100, and shift half the population across, but even then, thats going to take a hell of a lot of work to achieve.

Keith Armstrong

28 January 2011 at 15.26

The Institution has kindly published several of my letters on this subject over the last few years. Others have written in support or written on similar lines. It is hard to get Politicians to realise that the earth is of limited size and if we don't control population we shall run out of space and farmland sometime. The UK has had more people than it can feed since 1800. Malthus raised this problem about 1740!! We must either control numbers or many will die, it is that simple. It seems that those who can take some action are very slow to learn.

Andrew Taggart

29 January 2011 at 10.13

Laudable report but unlikley to make an impact. As engineers we need to be more media savy. We have identified the issues now we need to press home the value we offer in solving the problems.

John Attree

31 January 2011 at 19.19

Planet earth is a limited resorce. The real problem here is one of sustainability, and only one side of the equation is being addressed. The report addresses the supply side but nobody is looking at the demand side. The problem of controlling population growth maybe more a political one than an engineering one - but it does need facing up to.

Phil Robbins

01 February 2011 at 11:26

Interesting to read this article having attended the IMechE's climate change debate in 2009. At the time I asked the panel whether we were arrogant to assume that we could engineer ourselves out of a problem that engineering (or industrialisation, urbanisation or whatever you want to call it) has got us into. The answer was, unsurprisingly, 'of course we can'.

The problem I see is a reluctance to compromise various aspects of our lives in order to instigate real, measurable change. We need a global shift in attitude towards consumption, i.e. towards a simpler, less material way of life, which is not going to happen while so many countries are still ‘developing’. And even if we are successful in doing this, a 50% increase in global population will offset any benefits.

Our best bet is to accept that there are too many political and social barriers to attaining a truly unified approach to these problems and instead focus on engineering protection for those most vulnerable.

John Roberts

01 March 2011 at 08:51

It is well documented that the Indian Government has launched an urgent initiative to curb population growth following the birth of the country's billionth baby, there has also as we know been a reduction of populations in many country’s, once the governments see the light, and focus on the long term issue, (Not that long term) the author (Dr John Bongaarts) of the document clearly has the world best interest at hart, in my experience the lac of understanding from the movers and shapers clearly need refocusing, I would welcome the intervention of, “engineers” to show the way forward, designing “Best practice” and a blue print of advancement.

Lets do it.

Reaph Ltd


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