Iceland is keen to make a profit from its abundant renewable energy sources.
To do this it is flooding a large area of pristine wilderness to create a dam to power a new American-owned aluminium smelter.
But the project has fierce critics who are angry that Western Europe's largest wilderness is paying the price for Iceland's industrialisation.
We asked for your comments on the issues that our programme raised. A selection of your comments are below. This debate is now closed.
Quoting engineer Sigurdur Arnalds: "The sole purpose of all of this is to sell electrical power to foreign industries. If you look at it globally, this is clean energy." I believe this is utterly false, especially when raw materials must be shipped from halfway around the world (as with the ores shipped from Australia). Industries in polluted areas have less incentive to develop low carbon energy sources if they can "cut and run" to low carbon economies like Iceland's. Moreover, damming rivers is not so green. I used to think hydro-electric was clean, but considering all the mess in China, and the mess in northern Canada (and other places) and the way corporations and industries are so cavalier about "extracting wealth" and moving on, leaving local agencies and citizens to cope with the pollution, I no longer think that hydro-electric is such a great idea. Love your show, thanks.
T Newson, San Francisco, California, US
I visited Iceland last year and read something of the dam. It always seems a shame that real unspoilt nature is ruined for the want of an industry. Years ago we had a similar problem with a hydro dam in our South Island. Increased generation was required for a smelter. Fortunately, protest limited the development and preserved some beautiful scenery. Years later they further developed the underground generation facility without any environmental impact. Aluminium companies always seem to want cheap power. Often I am sure the building of a new smelter in a "cheap power source" country means closure in another country that once was cheap. It is a modern dilemma that the countries that can provide the cheap power often are beautiful and unspoilt as Iceland largely is. It would be nice to keep it that way but then again people need jobs to survive. Can't be a bad thing all together.
G Hansen, New Zealand
I went to Iceland last summer after Icelandic environmentalists called out for help in stopping the Karahnjukar dam. I have seen the beautiful wilderness that is unimaginable in the UK. It really was awe inspiring. This ugly dam that has ruined the area and signed the death warrants to hundreds of reindeer is an abomination. To think that there are preparations underway to build more is shocking. We all have a duty to stop this madness.
Pam Jones, Stirling
Mega-hydro dams are confusedly named renewable energy, while in fact they have a very limited lifespan and produce carbon emissions in similar quantities to fossil fuel generated electricity, because of methane emissions from reservoir heads. So the real question is: does Iceland want to sacrifice its natural beauty for climate hazardous, non-renewable energy?
Jaap Krater, Netherlands
It will not contribute to global warming but it does has a big environmental impact. And the area is far from dead and colourless, in fact, you would be amazed by the colours. Iceland has a responsibility to preserve some of the most unique places on this earth for future generations. Sacrificing that for a short term gain is simply not justifiable. Some places though, in Iceland, are not so unique and those we can and should use. It is just a question of what we should use it for. Using up all our clean energy resources to build one smelter after another is not something we want. What we want is to build up a versatile hi-tech economy capable of competing with the rest of the world.
Ingolfur Hermannsson, Reykjavík, Iceland
My concerns are more global, if we do not use our green energy, the aluminium plants will move to Brazil or similar places where non-green energy is used. So when the local members of the "Green party" talk about the environment they forget the global impact.
Hannes Thorisson, Reykjavik, Iceland
Surely the destruction of a wilderness and a river is not green, neither are fumes from the aluminium smelter. The environmental destruction is huge and goes far beyond an area being covered in water. In other places in the world dams have had huge negative impacts. I have been to the area that will be flooded and it is filled with incredible landscapes, reindeer, waterfalls, hot pools, violent rivers, diverse birdlife. It saddens me that all that beauty will be destroyed for the progression of an economy and heavy industry, and that people can call it green energy.
How free is this lunch? Where's the ore come from and how much pollution is created to get it there?
D Bulow, Vermont, US
The so-called renewable energy of Iceland is not automatically all renewable and certainly not without environmental costs or damages. Dams fill up and this process happens rapidly where there are glacial rivers because they carry a lot of mud. Similarly the geothermal areas may cool down if the heat is drawn too rapidly up. So the lifespan can actually be relatively limited. The term sustainability is totally out of place. Do not believe the slogans of the energy industry nor the government propaganda. Even though it is true that Iceland is blessed with a lot of natural energy it is not a matter without complications to harness it.
Steingrimur JS Igfusson, Iceland
I've been to all the sites of this project, the dam, the power plant and the smelter and I can't see why this shouldn't be done. The power plant will be underground, the water will be transferred underground and the space for the power lines and the smelter is not all that important. Flooding the desert closest to the glacier will be good for the highland around it. Also more use of aluminium will save energy in transportation and therefore it will contribute to the world's better climate.
Julius Sigurthorsson, Selfoss, Iceland
Besides the harm that is done to the landscape, vegetation and wildlife, this "dam" will be useless in some 50 years, due to erosion. There is so much to say about the risks and disadvantages, that it's too much to mention here. And even if it was green energy, why not use it for something fruitful, instead of an extremely polluting foreign aluminium smelter? If all the Icelandic potential of geothermal power was exploited, it could serve electricity for the whole of Europe. Doesn't this mean this "possible" source should be treated with the utmost care instead of ruining it all, only to add to global warming?
Deborah Miller, Antwerp, Belgium
There really is no need to build more aluminium smelters here in Iceland right now. The economy is soaring, everybody has more money than ever in the country's history. Why not wait? Why take desperate measures to make more money? People will need energy, preferably renewable, even in the distant future. This is plain greed and I am ashamed of my government.
Kolbeinn Hugi, Reykjavik, Iceland
Contrary to popular opinion and knowledge, dams are far from green or renewable. Dams turn gushing, nutrient rich rivers into dry beds; preventing fish migration, depleting silt emissions and accelerating climate change. The vast stagnant reservoirs drown vegetation and produce methane, which have been shown to have a greater greenhouse effect than equivalent coal fired power plants. As well as using real green energy, we must reduce consumption and localise production for efficiency and sustainability. Dams are dirty, expensive, inefficient and ecologically disastrous. I urge all Icelanders to research their effects in other countries before supporting this expensive ecocide.
Miriam, Kathmandu, Nepal
The multinational heavy industry is a big problem in modern society. It's eating up the world's natural resources to make profit for share holders. Destroying the wilderness is not a solution. It should not even be an option. Iceland is practically giving away its energy, making it cheap and easy to create more waste instead of encouraging the aluminium industry to recycle what we already have.
Arnar Steinn, Reykjavik, Iceland
This is how it all starts - with a "one-off" project for the "good" of the community. Before one knows it 10 other such projects have sprung up causing irreversible damage to the area not to mention "man-made" accidents and other natural calamities. Are we aiming to occupy every single piece of land possible on our planet which is already crying out for the damage we have caused by deforestation, oil spillages and so on?
For the love of God have we not just had a summit with all the world leaders agreeing that we need to address the issue of global warming? Again it's all down to money. When are these idiots going to realise that they can make all the money they want but they as the rest of us, will perish if we let these money grabbing fools get their way.
John Klapwijk, London
The master plan of changing Icelandic wilderness into the greatest smelter in the world comes before global warming. It is a old Stalinist dream of Icelandic engineers. Five aluminium smelters would finish all we have of waterfalls and untouched geothermal areas. It only contributes to more global warming. Cheep energy in Iceland contributes to a world of waste. We will not make money from the billion dollar project, it goes to the contractors. It goes to Alcoa. Journalists and readers have to help us stop this.
Andri Magnason, Reykjavik, Iceland
I think it's pretty stupid to use all this energy to power an American aluminium smelter. All this energy could be used to power a city the size of Manchester.
David Hendrikson, Akranes, Iceland
Keep the wilderness as it is, but make use of the renewable energy in the most lenient way possible to preserve what little is still pristine.
Green energy is not the only issue. The air quality in Iceland is superb, so one of my main concerns is the pollution from the aluminium plant itself, as these are known to be particularly noxious (I live near one!). But if the land for the proposed dam is indeed a wilderness in the sense that no other life uses it, why not use it productively for human purposes? My other main concern is the inevitable increase in pollution from the increased shipping at the nearby port and from the human pollution in the expanding manufacturing community.
David, Cheshire, UK
Unproductive wilderness? Excuse me, but isn't the wilderness what provides us with oxygen, fresh water and ultimately food? The true solution is to use less energy, and accept the surroundings in which we live. If people live in a cold country, they should not expect to have 20C inside their homes. And one thing is for certain, humans can't eat aluminium or electricity, and if we continue down this path, food will be again the main worry of humankind.
Alejandra Moreno, Mexico
I think most Icelanders weren't really aware of how gigantic this dam was going to be, and are now feeling guilty when it is too late. People can agree and disagree, but for me as a student in biochemistry, I see no other choice than to use the power which this country gives us, but in moderation. Since Landsvirkjun began this construction, the roads on the highland, and places of interest in the region have become more reachable so people can now really enjoy the landscape (the rest of it). With everything: there are pros and cons.
Johann Gretar Kroyer Gizurarson, Reykjavík, Iceland
I did a motorbike tour of Iceland's wilderness a few years ago and the place was largely full of nothing really. Vast areas resembled a giant quarry with no life, even plant life. I accept that green energy is a total must for the planet and if there is any landscape that must be "ruined" by our advances, then surely the "no life anyway" landscape of Iceland is a good candidate. We must all contribute to energy saving but whilst we need aluminium, we must have huge power resources to extract it from bauxite, the rock aluminium comes from. There is a big picture to consider, a very big one.
Will Sleddon, Chester
It is not only a question of whether or not to share Iceland's renewable energy with the world. I agree with the view that every nation has a moral duty to contribute to the improvement of the global environment. However, while environmental campaigners want to preserve the wilderness (almost) no matter what; the important question in my view is the use of this "clean" energy. Do we want to utilise the vast hydroelectric resources to attract "old fashioned" energy intensive heavy industry to Iceland or do we, the inhabitants of "Europe's largest wilderness", want to commit our "clean" energy resources to explore and attract knowledge-intensive, high technology and research-oriented industries to Iceland?
Einar Jorundsson, Reykjavik, Iceland
I strongly believe that green energy, and generally anything that significantly improves the environment globally with a small local cost, should be pursued where possible. I hate the "not in my back yard" approach, when that backyard is overall the most reasonable and safe place to put something that improves the lives of many.
Tivadar, Bremen, Germany
As some countries are rethinking their dams, and even dismantling them in some cases, and with plenty of aluminium facilities, as well as recyclable aluminium available, I would urge the people of Iceland to proceed slowly and cautiously with expansion. One dam and one smelter are enough. It does not have to be an either/or but at some point some places need to be kept wild. Once developed, it is hard to go back.
Lee Bellavance, Amsterdam
We must face reality and stop hiding our heads in the sand. Unless people are prepared to scrap their car, turn off their power and stop buying manufactured products completely then we need to use all clean energy we can find. At least until we acknowledge and fix the real problem: global overpopulation. The world would sustain 1 billion people, it cannot sustain six Billion.
Jim, Swindon, UK
The comments we publish are not necessarily the views of the BBC but will reflect the balance of views we have received. It is helpful if contributors state if they work for any organisation relevant to an issue discussed. Readers should form their own views on whether messages published represent undeclared interests, or views prompted by a common source.