Thursday 26 February 2009

Renewable energy: the possibilities

I've been reading Monbiot's book, Heat and the chapter on renewable energy is amazing:
Did you know that 62% of the energy generated in power stations is lost?
Here's some interesting stuff about the technology available now and what we can do with it:
- DC cables are now cheaper than AC cables and they have a major advantage: they can transmit energy across large distances without losing it. Ever wondered why these electricity pylons are so big and high up in the air instead of being buried underground?
The answer is the heat they generate: quite simply, to cool the heat generated by these cables, you would need the equivalent of 2 football stadiums underground back to back. That loss of heat is how the energy gets lost. It's the same concept as for incandescent light bulbs: they're only 90% efficient because they let so much heat escape. Why are these cables revolutionary?
If you can transmit energy over a longer distance, you can install the sources of energy much further. For wind power, this means that we can have large offshore wind farms that have large blades generating more noise and producing more energy offshore where no one will complain about them. More than 100% of our electricity in the UK could potentially be produced from wind so long as we can make adequate changes to the grid. For solar energy, it means that we can have solar panels in the sahara desert producing enough electricity for all of Europe.
The economies of scale that could be generated from both these technologies could enable it to compete with the price of brown energy and in the long run make it much cheaper.
Another interesting technology is solar thermal electricity: it's basically reflective dishes that focus the heat from the sun onto a tube containing water or another liquid. This reaches temperatures of about 400 degrees and the steam drives an engine which generates electricity. They've existed in California since the 80s. Their output costs in between 7 bto 9 pence per Kwh this compares to a current average price for brown of 10-15p per Kwh (Source: consumerfocus.org.uk).

Wednesday 25 February 2009

The Energy problem

We're making progress. President Obama in America has clearly set the agenda on renewable energy as the nation's priority. Since America is the second biggest polluter in the World anything that reduces the impact it has on the Planet is good news.

We have a massive problem with energy, it's not just the lack of or insecurity of supply, it's the use that we're making of it. Most people can easily see that their cars pollute through engines that burn fossil fuels but I wager most would be surprised to know that car pollution, as bad as it looks actually creates less pollution than cattle and the energy used in our homes. The dirtiest type of energy we use to generate electricity is coal. Coal generates twice as much pollution per kilowatt than the average of all the other forms of generating energy we use. 36% of our electricity comes directly from coal. Such is the urgency to reduce our emissions that this figure should already be zero. Our priority has to be to get rid of coal as a means of generating electricity ASAP.

It is very surprising on that basis that Eon is advocating building a coal power plant in Kingston. You can oppose this by visiting: http://www.nonewcoal.org.uk/. Don't believe the stories in the media about clean coal generation, there is not one power plant in the UK that generates clean coal or sequesters the carbon it emits. Clean coal is an oxymoron.

Instead we need to focus on massively increasing our investment in renewable energy. Renewable energy represents only 1% of the UK's energy capacity. Don't count on government to turn things around. I refer you to the book Heat by Monbiot to get an understanding of just how useless the UK government is and will continue to be at reducing emissions unless its citizens push for change. The only entity we can count on to pioneer change is ourselves. We are extremely fortunate in the UK to have a company that has understood the challenge we face and offered us an opportunity to change our ways. This company is Ecotricity. I believe it is the only company in the world that offers what it does.

There are 6 major players in the energy supply market and none of them is making an effort to increase the nation's renewable energy capacity. The government has requested 5% of their energy come from renewables and only one of these companies has 7% of their energy coming from renewables. They are heavily advertising themselves as being at the forefront of the green revolution!!! 2% more than the rest...

There are 3 key companies in the renewable energy supply sector: green energy, good energy and ecotricity. Of these 3 companies, Ecotricity is the only one that is directly investing in renewable energy. As a matter of fact, they are the only company in the UK that reinvest 100% of the client's spend into building new renewable energy capacity. This is no short of incredible; for someone seeking to reduce their carbon footprint, becoming an Ecotricity customer can make a huge difference.

The average UK citizen's carbon footprint is 12.5 tonnes in direct and indirect emissions. The footprint from electricity per home is only 1-2 tonnes a year whilst the average home generates about 6 tonnes of carbon a year. In 2008, ecotricity was able to remove an estimated 1.75 tonnes of carbon per customer from the atmosphere. This year however, based on the figures on their website and assuming a growth of 1000 customers per month, the average removal of carbon per customer will work out at 5.4 tonnes per customer, almost equivalent to the home's entire carbon emissions. That's an offset of 2 to 3 times more than the actual average household electricity consumption. It almost solves the problem of having to use gas for heating (for the time being only).

I can't stress how impressive that is. I've been investigating the possibilities to reduce our global emissions and the installation of renewable energy to replace coal use is by none the most effective and most realistic option we have available at this point. I had a high opinion of trees but unfortunately trees will not really sink a significant of carbon until 40-50 years in the future whilst they are very useful to fight the future flood problems we'll have along with generating oxygen that will gradually disappear as the rainforest gets the chop, they're not the solution to the drastic and immediate changes we need to make to avoid the catastrophe of runaway global warming (by this expression, we mean that above 2 degrees, nature will start producing vast quantities of carbon in an unstoppable loop and by 2100, will produce more carbon than human beings do thereby exacerbating global warming). Even the Energy Saving Trust recommends that if you are trying to offset your carbon footprint, you need to look at renewable energy projects where the carbon emissions reduction is visible rather than anything else. Find out more about carbon offsets here.

At this point, an important question must be raised: why is it that for the last 10 years Good Energy and Ecotricity have been around, their customer base adds up to less than 70000 homes?
Green electricity is a little more expensive than traditional energy but not massively. Why then? For one, these companies lack a direct sales force. For two, the average UK citizen just does not understand how serious the global warming problem is and they lack the understanding of what they can do to turn things around. It's down to individuals to change the world not governments or companies. Governments follow individuals, they don't take risks. It takes a massively charismatic leader to take political risks and one that can withstand the full blow of the media frenzy and voter loss of support when taking challenging decisions. I can't see one of those in the UK political landscape. Don't count on an Obama down here anytime soon. Understandably, politicians prefer not to gamble away their careers. They are after all in the majority, not idealists but negotiators and in the end, career people.

So unfortunately, Ecotricity has failed to meet its goal of supplying 1,000,000 customers by 2010 by a landslide and generating 500 Mwh of capacity. It's not too late, we can all support Ecotricity, all we have to do is become a customer.

Climate change and the media

Extract from Al Gore's Inconvenient Truth, 2006:
"Isn't there disagreement among scientists about whether the global warming problem is real or not? Not really. There was a massive study of every scientific article in a peer reviewed journal written on global warming for the last 10 years and they took a 10% sample, 928 articles. The number of those disagreeing with the scientific concensus that we're causing global warming and that it is a serious problem was ZERO. The misconception that there is disagreement about the science has been deliberately created by a relatively small group of people. One of their internal memos leaked and here's what it said: our objective is to reposition global warming as theory rather than fact. Have they succeeded? There was another study of all the articles in the popular press over the last 14 years. They looked at a sample of 636 articles. 53% doubted that we were the cause."

The more I read about climate change the more I am astonished at the lack of discussion and lack of programs about it in the media. We are at a critical point: if we don't do more about it within the next 4 years, the damage will be irreversible. It may already be irreversible. 2009 may be the first summer with no arctic sea ice in Greenland. So what you say? No arctic sea ice in Greenland means the biosphere has lost part of its ability to sink carbon and that the golf stream current will stall. In other words, the disappearance of the arctic sea ice means the onset of our species becoming extinct. Why is there not more media coverage about that?

In my view it's down to the news culture. News is about what happens now, not what will happen and it is what we are being fed on TV every day. There's a complete lack of foresight in the British media that is both appalling and worrying. The media plays a key role in informing the population and if the population is not well informed enough then they can't be prepared for climate change or be motivated to do anything about it.

Take for example the recent articles in the Times and the Mail deploring the loss of incandescent light bulbs or questioning whether we should continue recycling paper considering the market for it has collapsed. This is outrageous! Have they not heard of deforestation contributing to 20% of the worldwide emissions of carbon or of the ever rising levels of carbon in our atmosphere threatening our species of extinction? There's so much wrong with our culture I can't even begin to express my disgust.

Here's some evidence of The Times's campaign to deny climate change and to encourage people to do nothing about it (an action which in our opinion is equivalent to denying the Holocaust or if we put ourselves back at the time of that event: encouraging it):

Read the published section of have your say on articles about the environment: The Times always advertises predominantly negative opinions on articles related to climate change.

18/3/09 Anger as Shell reduces renewables investment, 2/3 comments are negative.

Yes, Joe, edinburgh - Greens should put their money where their considerable mouths are. The trouble is - like all socialists - they only want to play games with OTHER people's money.

JohnW, Manchester, UK

The oil companies are making sound business decisions.

It's enviros who are the hypocrites - Wind projects have high initial CO2 usage and noise pollution; Hydro CO2 usage, flooding of production areas and water shortage downstream: Solar CO2 usage and equipment disposal problems. Main Scam is CO2

Jim Talbot, Auckland, New Zealand

Tuesday 24 February 2009

The real problem of carbon capture

There are 3 stages to saving ourselves from certain extinction:

1- Reduce our carbon emissions
2- Eliminate or overcompensate our carbon emissions through offsets
3- Find a way to recuperate and trap the carbon we've emitted over the past 50 years

Reducing and eliminating our carbon emissions is possible. We live in world that's taken a long time to realize there was a problem with our emissions but things are looking much better now than they were 3 or 10 years ago. The government is advertising energy emissions reductions, the media has ongoing programs and articles on the topic and the industry is receiving investment. All this is very slow in comparison to how
quickly we need to make these changes but at least we're moving forwards.
The trouble with climate change is that it is a function of the carbon we've emitted over the past 50 years and it is a function of the carbon we are going to continue emitting. The level of population is already unsustainable at current carbon emissions and resource consumption per capita levels. Ideally we need 500 million people and we have 6-12 times more. By 2050, we'll have 9 billion people at current population growth rates, 9-18 times more than the planet can sustain. Looking at the growth in carbon emissions of our civilization, it is likely that these 9 billion people will emit more carbon than we are now.
Even if these people somehow manage to emit zero carbon, we're still going to have a problem because temperatures will continue rising and with as little as a 2-3 degrees average global warming, 2-3 billion people will be without water. Can we let these future generations die?
No, not if we have just an ounce of compassion in our make up. So we need to regulate births in Western countries, that's about as important as trying to cut carbon emissions to make room for those future refugees. And if anyone's worried about lack of younger generations to pay for other's retirements; don't worry: with climate change we'll have plenty of immigrants just begging to come to work here because the opportunities in their part of the world will have all but disappeared thanks to us importing our rotten development model. We owe them at least a new home so we should start making space.
Now let's assume we do 1 and 2 and we manage to live in a world without human carbon. It's not impossible you know. What then? Well because of the increase in temperatures, Nature will be generating more carbon than it used to. This will come from increased fires, forest loss, methane released from the permafrost, methane released from the oceans etc... So the one problem that no one seems to be addressing right now is: how are we going to trap all this carbon to avoid ever worsening climate change?
This is the one area where we really need to pin our hopes on science and on our collective intelligence. So far there has only been talks about carbon capture in respect of continuing to burn fossil fuels. Talk about carbon capture is related to trapping the carbon emitted by power plants such as coal plants in depleted gas or oil fields. But there has been no talk about how we can reduce the current 380 particles per million (ppm) of CO2 to the much more sustainable 280 ppm we had just 500 years ago. And that's what we need to address to avoid runaway or positive feedback climate change.
First we need to find a place where to stock all this carbon. The good news is we've found a spot, it's on the Eastern cost of America, under the ocean. Second we need to drill that area and get a pipeline running from North America to the Ocean to send all that carbon down below the Earth's crust. Third, we need to invent a gigantic particle hover(s) that can hover up everything in the atmosphere, filter out the carbon and spit out the rest. That's where we've come unstuck, I have not heard a single report of anyone even researching that option.
So if you're a brilliant scientist, forget about re-conciliating general relativity with quantum mechanics and please focus on saving our arses pronto please.

Finally, I mentioned methane earlier in this article. We have huge amounts of methane available almost everywhere on earth and especially buried in the oceans. Methane is the main ingredient used in the production of natural gas that can be used to power vehicles. The only reason why we are not using it now is because of accidents which made it seem less safe than oil or coal. All our vehicles could be running on natural gas. As a matter of fact, all public transport in Bangkok Thailand now runs on natural gas. For an equivalent amount of heat, burning natural gas produces about 30% less carbon dioxide than burning petroleum and about 45% less than burning coal. According to wikipedia those reduced emissions do not include the methane released in the atmosphere in the drilling process (methane units pollute 23 times more than Co2 units). To me it would make a lot of sense to drill methane where it is likely to naturally evaporate into the atmosphere due to global warming ie in the permafrost and in the arctic circles. If that methane is burned and provides us with more eco-friendly transportation at the same time as we avoid its release into the atmosphere, then it should be much more beneficial to us than burning oil or coal.

Tuesday 17 February 2009

Some key Statistics and facts

Over 50% of the world population is now urbanized according to the United Nations. The majority of people are out of touch with the natural world.
The levels of carbon dioxide and methane in the atmosphere are now higher than they have been for 650,000 years. (Source: The economics of climate change 2006, Sir Nicholas Stern)
Carbon dioxide levels have been rising over the past century faster than at any time over the past 20,000 years. (Source: The economics of climate change 2006, Sir Nicholas Stern)
The increase in temperature in the twentieth century is likely to have been the largest in any century in the past 1000 years. (Source: World Meteorological Organization, The Eddington Transport study 2006)
If everyone in the world lived like we do in the UK, we’d need three planets – not just one. (WWF Website)
There are over 32,000,000 million vehicles in the U.K.
On average 24.6 miles are driven every day by single user vehicles.
Over 400,000 tones of carbon dioxide emissions are pumped into the atmosphere every day. (isanyonegoingto.com)
Over the last century the total mass of vertebrates has halved. Meanwhile the mass of humans has quadrupled. (The Planet documentary)
Since 1990, China's emissions have increased by 67%. The figure for India is 88%.
A single European consumes 50 tonnes of our planet's resources every year.
The level of CO2 in the atmosphere today is the highest is 750,000 years.
The 22 warmest years ever recorded have occured since 1980.
96% of all surveyed glaciers around the world are currently diminishing in size.
In Western China, 300 million people rely in whole or in part on glacial meltwater during the summer to irrigate their crops. What are they going to do? This is fossil water, they're not going to get it back until the next ice age. The disappearance of those glaciers alone is enough to cause a net food defcit and a global humanitarian catastrophy.
Over one billion people are already suffering from a shortage of clean water.
In 2010, 50 million people will be trying to escape the effects of environmental deterioration.
Natural disasters have increased more than fourfold over the last 40 years. Windstorms, fiverfold. Flooding sixfold. Bushfires tenfold.
What you do now happens in 50 years time with the climate.
CO2 emissions from U.S. coal-based electricity are greater than emissions from all the cars and trucks in America. (“GHG Emissions and Sinks 1990-2006,” US EPA 2008)
There are roughly 600 coal plants producing electricity in the U.S. Not one of them captures and stores its global warming pollution. (“Electricity Facts,” US DOE 2008 (link); IEA Greenhouse Gas R&D Programme CO2 Capture and Storage Database (link); Carbon Capture and Sequestration Technologies Program at MIT, CO2 Capture and Storage Project Database (link))

Monday 16 February 2009

Why Chinese-made products must be boycotted by Western Consumers

“China is still a developing country and the present task confronting China is to develop its economy and alleviate poverty, as well as raise the living standard of its people,” foreign ministry spokesman Qin Gang told reporters.

“Given that, it is natural for China to have some increase in its emissions, so it is not possible for China in that context to accept a binding or compulsory target.”

11/06/2009, Source

China is responsible for 20% of global greenhouse gas emissions. China in 2006 became the biggest emitter of greenhouse gas emissions in the World. Over the past decade, China was able to lift 500 million out of poverty into the middle class. As a developing country, China is not required to reduce its emissions. China mainly relies on fossil fuels, particularly coal, for energy. Over the next 10 years, China will be building 500 coal fired powered stations. Every 4 days, China is opening a new power station. To give you an idea of the scale of these constructions, the United States has 600 coal fired power station whilst the UK only has 17 but they supply 33% of its electricity.
Dermot O'Gorman, WWF China Country Representative, said that "Developed countries who benefit from importing goods instead of domestic production are also responsible for the rapid growth of China's energy consumption and greenhouse gases emission. It's unfair to put the blame on China for the large emission of greenhouse gases."
Chinese officials have recently stated that they are not prepared to put greenhouse gas emissions ahead of growth on their agenda. In the same way as Western countries have dramatically failed to decrease their carbon emissions and meet the Kyoto protocol Traty targets, China is failing to reduce its own.
It seems obvious to me that as Western consumers eager to purchase cheap goods, we must refrain from purchasing as much as possible anything produced in China until China commits to reducing and managing its carbon emissions properly.

David Attenborough's view on Climate Change

What will happen in the US and Botwana when the sand dunes are awaken by global warming

Sunday 15 February 2009

The Purpose and Importance of Trees

"A tree makes oxygen, sequesters carbon, fixes nitrogen, distills water, provides habitat for hundreds of species, accrues solar energy, makes complex sugars and food, creates microclimates and self-replicates." The 11th Hour



I'm not a tree hugger or a tree lover. The only relationship I had with a tree was when I was smaller and my dad helped me to build a tree house in our garden. Many years later, I was upset when acid rains destroyed the leaves on the tree in spring.
Recently however, I have rediscovered the importance of trees in looking for ways to reduce people's carbon footprint. If you think about it, in economic terms, trees are worthless except for fruit trees they're really not going to make anyone richer are they? Well actually, I've found that trees are much more useful than I previously thought, here's why:
- They produce oxygen through photosynthesis. The Amazonian rainforest generates 20% of the world's atmospheric oxygen.
- They sequester carbon. A word of warning here: you can use trees to offset your current carbon footprint but a tree does not begin to absorb carbon until it has matured which takes 15 years. So if you're trying to offset your carbon footprint with trees now, you need to realize that you're offsetting it decades forwards. A tree over its lifetime will absorb about 1 tonne of carbon. Also, each tree planted may not survive for its full lifetime so if you're trying to offset, you need to consider where the trees are planted and how many trees to plant. Worldwide, 10 trees are cut down for every tree that is planted. If you donate for trees to be planted, make sure the area in which they are planted is protected. I also like getting trees planted in the UK because no matter how un-environmentally friendly we are, I trust UK regulation and efforts for protecting trees more than the ones in the developping world. For instance, in Brazil, 80% of the logging is conducted illegally.
- They prevent erosion: you only need to look at Haiti to understand that. The level of deforestation in Haiti is perhaps one of the worst in the world. The contrast in between Haiti and the Dominican Republic when you look at helicopter views of the frontier is astonishing: on one side you see a huge forest and on the other you see barren land: the inhabitants of Haiti have completely deforested the land to provide for their needs. Add to this the fact that with global warming the oceans are warmer and thus hurricanes are stronger and more frequent and you have a recipe for disaster. Just last year, in September of 2008, Haiti was hit not by one but by 4 hurricanes. This was the worst natural disaster the island has ever known and it was compounded by the absence of trees. A tree can retain 57000 gallons of water in a 10-12 inch flash flood. It can grab that much water, prevent it from running off, cleans it and puts it back in the aquifer. During the hurricane season, a huge amount of soil was displaced into the sea. Soil takes from 100 to 1000 years to settle in any given area so it will take that long for the ecosystem in Haiti to recover. In a world with finite fertile soil, its preservation is essential to our survival. Only 20% of the soil on land on our planet can be cultivated. Furthermore, the soil that runs into the sea at each hurricane season disturbs the ocean ecosystem killing all the fish. When you know that the average inhabitant of Haiti lives on $1 a day, imagine the scale of the disaster acknowledging that they can't hunt in the forest anymore and that there are no fish left on their coast! The same could happen to us in the UK if global temperatures rise by 3 degrees. Hurricanes may begin to hit our coasts along with flash floods. That's a very good reason for us to plant as many trees as we possibly can.
- In addition to the 3 key benefits mentioned above trees also distill water, provide habitat for hundreds of species, accrue solar energy, make complex sugars and foods, create micro climates and self replicate.
- Trees also produce clouds and clouds produce rainfall.
- Finally, forests are the lungs and the water tanks of the planet. Read more here.

Watch a film to find out what some organizations are doing to solve the problems of deforestation: click here.

News on Deforestation:

The UK Government Eliasch Review calculated that allowing deforestation to continue could cost the world $12 trillion and called for emissions from deforestation to be halved by 2020 and to be carbon neutral by 2030. (Source: The Eocologist, November 2008)

Scientists have found
A fifth of the world's carbon emissions are soaked up by extra forest growth. Trees in the tropics are getting bigger, which means they are soaking up an extra 5bn tonnes of CO2 a year. Compared to the 1960s, each hectare of intact African forest has trapped an extra 0.6 tonnes of carbon a year. Over the world's tropical forests, this extra "carbon sink" effect adds up to 4.8bn tonnes of CO2 removed each year - close to the total carbon dioxide emissions from the US. Although individual trees are known to soak up carbon as they photosynthesise and grow, large patches of mature forest were once thought to be carbon neutral, with the carbon absorbed by new trees balanced by that released as old trees die. (Source: The Guardian, 18/2/09)

How to reprogram your mind to become an environmentally fridenly citizen

1- Forget that freedom of choice is a good thing
A friend of mine is fond of the following saying: "People are like rivers, they take the easy route". This couldn't be more true when we look at their food consumption patterns or indeed the consumption patterns in a wider "free" market. In a free market, people have a choice in between cheap mass produced products that are bad for the environment and more expensive environmentally friendly product. Which do you think is always going to be the larger market if people are given freedom of choice?
There is a French proverb that says: "la liberte des uns s'arrete ou commence celle des autres", literally translated this means that our freedom stops where the freedom of others begin. A liberal market is based entirely on the notion that freedom of choice is good. Is it a good thing to have the choice in between cheap mass produced foodstuffs and expensive organic ones? The answer is unequivocally yes for consumers and no for the environment. Since the environment is what enables consumers to survive; the environment's rights are more important than the consumer's rights however in a free market, the reverse is true.
What is the problem with mass produced foodstuffs? They use a lot of pesticides and insecticides which generate nitrous oxide. Nitrous oxide has 300 times the greenhouse effect of CO2 and is responsible for 21% of the greenhouse emissions from the food supply chain. That is the hidden cost of cheap vegetables and meat which is never expressed in the lower "subsidized" price we pay. That's why we need regulation so that people are no longer given the choice but are under the obligation to pay a higher price for their long-term survival. That is what we may call "sustainability" politics.
2- Having one more baby in the UK is very bad news
The current world population is 6.5 billion and it is supposed to stabilize around 9 billion by 2050. The World is already overpopulated and the annual biological debt accumulated by the World population is equivalent to 20%. That means we consume 20% more than what the Earth is able to cope with in terms of its ability to regenerate itself. The average life expectancy of men and women in the UK is equal to 79.5 years and the average annual carbon footprint of a UK citizen is 12.5 tonnes. Therefore the average carbon footprint of an individual in the UK is equivalent to 993 tonnes over their life time. The weight of an empty boeing 747 8i is 211.7 tonnes therefore the weight of the carbon emissions of a UK citizen is equivalent to 4.69 Boeings 747 . A rough estimate of how much it would cost to offset that carbon footprint by planting trees is: £30981 or 2581 trees, that assumes planting 2.6 trees to offset each ton of carbon at a cost of £12 (these figures were provided to me by Trees for Cities a UK based tree planting charity). There is simply not enough land available to plant that many trees for each new born. We have 2 choices: either we regulate births our impose upon ourselves not to have children or Nature takes care of it for us through famine and the spread of diseases.
3- Understand the idea of finite supply
Our entire free market culture is based on the idea that nature offers abundant supplies of everything. However, this is no longer the case. Based on proved and probable reserves, we are running out of almost every available raw material be that metals, oil, coal uranium or anything else you can think of that you might define as a raw material. The discovery of new resources is only delaying what we already know: soon and very soon in some cases we are going to run out of Nature's abundant resources. These are just the resources we rely on for our economy. The resources we rely on to live: water, soil, trees and oxygen are also running out due to intensive use and pollution whilst at the same time global warming through a phenomenon known as positive feedback is reducing further those resources naturally. Soon we may lose control over greenhouse gas emissions due to global warming releasing huge amounts of greenhouse gases trapped in soil, vegetation and oceans. Nature has got finite supplies of everything and unless we reduce the consumption of these finite supplies we will run out of the very essence of what makes our life possible on this planet.
4- Economic growth is bad news
Growth is an exponential function. Exponential functions in a finite supply & overcrowded world are self-destructing mechanisms; they can't last. In a recessionary environment, people lose their jobs and can't find work. It appears that to maintain full employment, there is no other solution but to promote growth. However, if restrictions are imposed on birth rates it is possible to have in the longer-term an environment with zero growth or negative growth yet still have the benefits of a growing economy since there are less people around to benefit from the additional economic wealth.