What should be done against Climate Change?
Although there are still some uncertainties, it is widely recognized that
global climate change is one of the most serious threats to the environment. If no action is taken to significantly reduce greenhouse gas emissions,
global warming is likely to have serious - even possibly catastrophic - consequences.
Unfortunately, there is no single action that will solve the problem. The first step would be to reduce the energy consumption in industrialized countries - by shifting the tax burden to CO2 emitting activities and products, by rethinking the planning of cities, and by improving public transportation. But also, CO2-friendly energy sources must increasingly be developed: renewable energies, CO2 underground storage, and nuclear power plants.
Actions could and should include all of the following:
- Reducing our energy consumption: a large reduction would probably
be achieved in the industrialized countries just by raising taxes on fossil
consumption - progressively but fast, in a planed fashion - and reducing other taxes, notably on employment, in exchange. The market mechanisms would play spontaneously,
bringing two benefits: decreased emissions of greenhouse gases and increased
Notably, plane travel has the highest production of CO2 per mile (about
as much CO2 per passenger as an average car
occupied by one person). It is competitive only because kerosene fuel is
not taxed: tax it, air tickets will become less cheap
and customers will choose more CO2-friendly transportation...
Unfortunately such actions alone would not be sufficient to reduce
greenhouse gas emissions: the energy consumption in developing countries is
expected to rise significantly faster than industrialized countries could reduce
- Better thinking of the layout of the cities would help reducing
the greenhouse gases emitted by transportation. Too often, office buildings
are located in
the center and residential areas in the outskirts, which create
dense peak hour traffic, long commuting distances and unnecessary CO2 emissions.
Instead, office districts should be distributed in several locations, closer
to resident neighborhoods and well connected by public transport. Unfortunately, this requires political common sense in urban planning, and decisions can only have an impact on CO2 emissions long after they have been taken...
- Improving public transport and rail freight: they are generally
poorly run by ineffective state-owned monopolies. Open them wisely to competition
and they will become better run, more attractive and play a greater role in
reduction. Also, measures
promoting carpooling are effective, such as "slugging" and
lanes reserved for "HOVs" (High
Occupancy Vehicles) available in many
cities in the USA.
- Developing electric vehicles: they are clearly the most sustainable personal transportation, as they use significantly less primary energy and emit nearly a quarter of the CO2 emitted by equivalent fuel vehicles (see the report published at www.going-electric.org).
- Developing renewable energies, including biomass fuels, wind turbines,
solar panels and geothermal energy. Although renewable sources could and should
be more utilized, there
are limits to their generalization at the present state of technology:
- Biofuels can be used right now in existing
cars and trucks, mixed with gasoline or diesel - and they make the
cleaner and reduce urban pollution. But they consume a lot of energy
in their production (25 to 75% of the energy recovered). They also require converting agricultural or natural landscapes for their production, impacting food availability and ecosystems. And they could only cover a fraction of our energy
- Wind turbines are also an excellent solution
in several instances. Unfortunately, if it had to become the only
energy source, a significant part of the land would be covered with
Also, wind turbines only work when the wind blows and therefore
should require expensive
energy storage plants if generalized.
- Solar heating panels are already very effective
for producing hot water or heating swimming pools. However, they are
less effective in cloudy weathers and during winters, when they often need to be
complemented with conventional heaters.
- Solar photovoltaic panels are already useful in remote locations
where mainstream electricity is not available. With current
technologies, their can only convert a very small fraction of the
solar energy available and remain very expensive. However, there is
a huge potential: more research will likely increase significantly theirs yield and reduce their
cost to the point where they could in a few decades
become a very
competitive source of energy: for instance, they could be used widely
in sunny regions to produce
We recommend that more money should be spent in developing photovoltaic solar
- Geothermal energy is widely used in some volcanic
countries like Iceland where it is easily available. There are probably
many other volcanic regions where it could be developed, possibly for
producing hydrogen (see below), but with current technologies the potential is limited.
- Storing CO2 underground: CO2 emitted by large sources, such as power plants, hydrogen production plants and some industrial facilities, could be purified then safely stored in underground formations. However, Carbon Capture and Storage is energy consuming and would therefore accelerate the depletion of our fossil fuel reserves.
Read the summary of the IPCC special report on Carbon Capture and Storage...
- Developing nuclear energy is, by
many aspects, the safest, cleanest and most sustainable energy source currently
available, with still
a lot of
for development. But with current technologies, nuclear plants increase the risk of nuclear weapons' proliferation, so they should be commercialized with the greatest caution (until fourth generation reactors are available). Also, the problem of nuclear waste need to find a solution: technically, it could be stored deep underground where it would remain safely for millions of years, but a a political agrement still needs to be found.
Hydrogen could be used as a fuel for transportation.
Its combustion is clean (it produces essentially water) and therefore would
reduce urban pollution.
However, hydrogen is NOT an "energy source":
it needs to be produced by other energy
sources. Because there are inevitably energy losses in its production, transport
and use, hydrogen requires much more energy to produce that it can deliver
in engines or in fuel cells.
But hydrogen could become a great "energy vector":
for instance, it could be produced in remote locations where an energy source
abundant (for instance by solar energy in deserts, geothermal energy, or with dedicated
nuclear plants). Then it would be transported to filling stations for distribution
to cars and
trucks - thus contributing to CO2 reduction. Some
technologies for producing, transporting and using hydrogen have been developed,
but unfortunately, more research and many more years will still be needed before
hydrogen can effectively become a widely used fuel.