1. O NS
T I
U ES &
Q WE RS
A NS le
w ab
Re ne
on rgy
E ne
www.solargeneration.org

2. QUESTIONS
=
== & ANSWERS
ON RENEWABLE ENERGY
1. WHAT IS RENEWABLE ENERGY? 3
2. WHAT ARE THE MOST COMMON RENEWABLE ENERGY SOURCES? 3
Wind 3
Solar 3
Biomass 4
Geothermal 4
Hydropower 4
3. IS RENEWABLE ENERGY MORE EXPENSIVE? 5
4. CAN RENEWABLE ENERGY AND ENERGY EFFICIENCY
MEET THE GROWING ENERGY DEMAND? 5
5. WHAT ABOUT RELIABILITY –
WHAT IF THE WIND DOES NOT BLOW? 6
6. WHAT ABOUT DEVELOPING COUNTRIES? WHAT USE IS IT TO
INVEST IN RENEWABLE ENERGY IF CHINA AND INDIA AND OTHER
RAPIDLY INDUSTRIALISING COUNTRIES BUILD A NEW COAL-FIRED
POWER STATION EVERY WEEK? 7
7. ISN’T NUCLEAR “ZERO CARBON” AND MORE RELIABLE? 8
8. WHAT ABOUT “CLEAN COAL” AND CARBON CAPTURE
AND STORAGE? 8
9. WHERE CAN I FIND MORE INFORMATION? 9

3. 1. WHAT IS
RENEWABLE ENERGY?
Renewable energy is electricity that is produced from sources that replenish
themselves naturally. There are five sources of renewable energy: wind, sun-
light (solar), landfill and agricultural waste (biomass), the heat of the earth
(geothermal) and water (hydropower). These renewable sources of electricity
have less impact on the environment than traditional methods of electricity
generation, which include burning fossil fuels such as coal, oil and natural
gas. Natural gas and coal, for example, are not renewables because
their use consumes gas and coal reserves at a much quicker rate
than they are replenished.
2. WHAT ARE THE
MOST COMMON
RENEWABLE
ENERGY SOURCES?
Wind, the world’s fastest growing energy sector with an average
annual growth rate of 28%, could provide 12% of the world's energy
by 2020. The industry is expected to generate two million jobs and f naked s
save more than 10 billion tons of carbon dioxide emissions. Hundreds os symbolife
er t
volunte erabilityro
Solar energy comes from the sun, and has the potential to provide the valners unde
u
i
several times the current world energy consumption if it can be he gl tc change, k
properly exploited. Solar thermal and photovoltaic are the two basic ima e cer Tunic
cl en
types of solar power. by Sp
Solar photovoltaic (Solar PV) generates electricity from sunlight by using
semi-conductor materials. Silicon, an element most commonly found in sand,
is the most common material used in photovoltaic cells. All photovoltaic cells
have at least two layers of such semi-conductors, one positively charged and
one negatively charged. When light shines on the semi-conductor, the electric
field across the junction between these two layers causes electricity to flow in,
generating DC current. Therefore, the photovoltaic system does not need
bright sunlight in order to operate. It also generates electricity on cloudy days,
with its energy output proportionate to the density of the clouds. Due to the

4. reflection of sunlight from clouds, days with a few clouds can even result in
higher energy yields than days with a completely clear blue sky.
Solar thermal is based on a simple principle: the sun heats up water
contained in a dark vessel, using the heat of the sun directly. Large mirrors
concentrate sunlight into a single line or point. The heat created there is used
to generate steam. The hot, highly pressurised steam is used to power tur-
bines, which generate electricity. In sun-drenched regions, solar thermal
power plants can guarantee a large share of electricity production.
Biomass refers to the utilisation of organic matter (plants, etc.) as fuel using
technologies such as gas collection, gasification (converting solid material to
gas), combustion, and digestion (for wet wastes). Potential problems such as
fuel from unsustainable sources, and releasing greenhouse gases while burn-
ing, are fundamental to biomass technology, and they can be avoided with
proper implementation. Furthermore, in areas with plentiful farmland, bio-
mass can play a major role in supplying heat and electricity.
Geothermal comes from the heat inside the Earth. According to estimates,
the Earth's core is incredibly hot - 5,500° Celsius (9,932° F). Power genera-
tion from geothermal causes virtually no pollution or greenhouse gas emis-
sions. It's also quiet and extremely reliable. Geothermal power plants produce
electricity about 90% of the time, compared to 65-75% for fossil fuel power
plants.
Hydropower, energy from water, running rivers or waves in the ocean, can be
harnessed and converted into electricity without producing greenhouse gas
emissions. It is a renewable energy resource because water is constantly
replenished through the earth's hydrological cycle.
Estimated by the World Energy Council, wave power could produce two ter-
awatts of energy each year, which is twice the world’s current electricity pro-
duction. The total renewable energy within the world’s ocean, if all harnessed,
could satisfy the present world demand for energy more than 5,000 times
over. Yet, the technology of wave power is still under development.
For river power, harnessing the energy of water going from a higher to a lower
level, the greater the drop in elevation, the faster the water flows, the more
electricity can be produced.
Large scale hydropower, such as big dams, can drown ecosystems. They can
cause shortages in the water needs of downstream communities, farmers and
ecosystems, and be unreliable during prolonged droughts and dry seasons
when rivers dry up or reduce in volume. Small-scale hydro systems, classified
as “small”, “mini” or “micro” by the amount of electricity production, capture the
river’s energy without diverting too much water away from its natural flow.

5. 3. IS RENEWABLE ENERGY
MORE EXPENSIVE?
As the market for renewable energy grows rapidly, renewable energy
becomes more competitive. For instance, wind power has shown up to a 50%
drop in production costs over the past 15 years. Now, at optimum sites wind
can be competitive with new coal-fired plants and in some locations can chal-
lenge gas. Thanks to continuing improvements in the average turbine size and
capacity, by 2020 the cost of wind power on good sites is expected to drop to
2.45 euro cents/kWh (per kilowatt hour) – 36% less than its 3.79 euro
cents/kWh cost in 2003. In addition, this does not even take ‘external costs’
(polluting costs) into account. If external costs were added to traditional fossil
fuel powered electricity, renewable energy would easily take up the competi-
tion. Since costs of CO2 emissions are now starting to be integrated into elec-
tricity prices (as in Europe), it won’t take long until renewable energy will
become competitive.
4. CAN RENEWABLE ENERGY
AND ENERGY EFFICIENCY
MEET THE GROWING
ENERGY DEMAND?
Energy [R]evolution, the latest report released by Greenpeace, addresses
details of how to halve global CO2 emissions by 2050 by using existing tech-
nology and still providing affordable energy and economic growth. How? The
answer to this is two-fold:
1. By sustaining the current double-digit growth rate of the global renewable
energy industry over the next two decades (approx. 30% per annum for
wind and 40% per annum for solar photovoltaic - both figures represent the
average of the last 10 years).
2. By introducing high technical efficiency standards for all energy-consuming
appliances such as computer systems, heating and cooling equipment,
and other high energy users such as road vehicles.
This combined approach will ensure that there is sufficient energy for a glob-
ally growing economy, equating broadly with the projection of the International
Energy Agency.

6. 5. WHAT ABOUT
RELIABILITY – WHAT
IF THE WIND DOES
NOT BLOW?
Most renewable technologies are not ‘inter-
mittent’. In fact only two of the five renew-
able energy technologies are: wind and
solar photovoltaic. All other renewable
energy technologies are reliable and
predictable, such as geothermal, bio-
mass energy and hydro-electric power.
In the heating and cooling sector,
fluctuating energy sources (in this case
solar collectors only) are not an issue, as it
is no problem to store heat.
And for wind: Actually, the wind always blows
somewhere (particularly off-shore and at heights), so
this issue is largely irrelevant with a proper electrical grid to
move power from one place to another. Modern power grids already transmit
electricity over hundreds of kilometres, and cope with significant fluctuations
in both demand and supply.
Of course, it is also a good idea to have a mix of power solutions - including
solar, bio-energy, and hydropower - to balance the strengths and weaknesses
of each source against the others.

7. 6. WHAT ABOUT
DEVELOPING COUNTRIES?
What use is it to invest in renewable
energy if China and India and other
rapidly industrialising countries build
a new coal-fired power station
every week?
China currently builds a lot of new coal-fired power plants – but it shuts down
a lot of older, more inefficient ones as well. The Greenpeace energy scenario
assumes that all coal power plants currently under construction will come on
line. This explains why this alternative scenario (which includes an increase in
the use of coal up to the years 2010 – 2015) is close to the “business as usual”
scenario. It does take a few years to change policy and switch to renewables.
The same is true for the development of the energy supply in India.
The alternative scenario assumes the same GDP growth as the IEA
(International Energy Agency) energy scenario does. In fact renewable
energy can “follow” the growing demand much better, as the planning & con-
struction time of renewable energy is a lot faster than conventional centralised
power plants.

8. 7. ISN’T NUCLEAR “ZERO
CARBON” AND MORE
RELIABLE?
No. Nuclear energy also generates CO2, if we take uranium mining into
account. Besides that, uranium is also a finite and limited resource. It is esti-
mated that the economically viable uranium will last approximately only 65
years for the existing nuclear power plants around the world. Besides being
non-renewable, nuclear power remains dangerous, polluting and expensive.
More nuclear power means more radioactive waste, more nuclear weapons
proliferation, more nuclear-armed states, more potential "dirty bombs" and
more targets for terrorists.
8. WHAT ABOUT “CLEAN
COAL” AND CARBON
CAPTURE AND STORAGE?
There is no such thing as clean coal. New
coal power plants are more efficient than old
ones – but this has been achieved through
technology developments over the years
because of hard competition with gas power
plants! Compared to gas, coal still emits
roughly twice as much CO2 per kWh than a
gas power plant – and due to technical rea-
sons, coal will never be as CO2-efficient as
gas. Proposed “CO2-free” coal power plants
are not CO2-free, they just remove the CO2
from the emissions – which wipes out
approximately 20% of the energy generated. So those power plants are less
fuel-efficient than “conventional” ones.

9. Carbon capture and storage, is complicated and only possible (if ever) for a
small number of power plants. This is because the areas that have a suitable
geology for carbon capture and storage are limited and unevenly distributed
globally. Clean coal is a “Trojan horse” to build coal power plants, and a sur-
vival strategy for mining companies. It will not be cost-competitive with renew-
able energy.
9. WHERE CAN I FIND
MORE INFORMATION?
http://www.energyblueprint.info/
http://www.greenpeace.org/international/solargen/about-solar-energy
http://www.yes2wind.com

10. NOTES

12. TESTIMONY
A PERSONAL IMPRESSION OF THE ‘RESTRAINT, EFFICIENCY, & RENEWABLE
ENERGY’ GUIDE BY SÉBASTIEN,
« When I started working on the ‘Sustainable
Campus’ project at my university, Euromed
Marseille, dealing with the energy theme, I must con-
fess that I was completely lost... I had no idea how to
approach things or where to start. The association had
already set up a feasibility study for the installation of
solar panels, but this did not necessarily seem to be
the logical first step.
I made some enquiries, particularly by talking to Solar Generation, and I found out
about an approach that had instant appeal because of its clarity and logic: this was
the ‘negaWatt’ initiative. This association advocates the following energy-saving
approach:
Restraint = consume less;
Efficiency = consume better;
Renewable energy = ‘clean’ production systems.
We therefore tried to follow this initiative as best we could. First of all, we tried to
reduce consumption in our school by teaching people on campus to become bet-
Greenpeace International Ottho Heldringstraat 5 1066 AZ Amsterdam Netherlands
ter eco-citizens. Then we put pressure on our administration to carry out an energy
diagnosis on its installations with a view to making them more efficient. This study
was carried out over a month and a half, and certain measures were selected and
should be put in place over time.
I feel that the first two steps in the ‘negaWatt’ initiative are quite easy to put into
practice and negotiate with management. Indeed, in both of these steps, the finan-
cial argument is a powerful factor. Quite clearly, we are saving our establishments
Printed on 100% post consumer recycled chlorine-free paper
money, so how can they resist?
The projects for the installation of renewable energy are more complex and time-
consuming, but they can be done. They require a financial investment which can
often be substantial – at least if we wish to achieve a significant reduction in our
campus’s impact. And persuading a School or University to invest is a major oper-
ation... The administrative procedures are complicated and technical aspects are
pre-eminent. Having said that, don’t hesitate to get involved, be ambitious,
www.solargeneration.org
because once you’re in there you can’t do without it, it’s a fascinating area to work
in, with some brilliant projects! Also, working on these themes as a team within the
Solar Generation network is a real pleasure.
Finally, as regards the ‘negaWatt’ initiative, I would advise everybody, if they have
the motivation and the means, to undertake the maximum number of measures at
the same time. But most of all, do yourself a favour and remember that Solar
Generation is there for you!