A practical guide to sustainable IT
paul Mobbs
A practical guide to sustainable IT
Unit 11
This unit is one of 12 sections to a "A practical guide to sustainable IT", a hands-on guide to working with everyday technology
in an environmentally conscious way. The guide has been written by environmental activist and ICT expert Paul Mobbs, and
was commissioned by the Association for Progressive Comunications (APC) with the support of the International Development
Research Centre (IDRC). To download the full text of the guide, or any of the other units, please visit: greeningit.apc.org
A practical guide to sustainable IT
Author
Paul Mobbs
Copy-editing
Alan Finlay
Layout proofreading
Lori Nordstrom
Publication production
Karen Banks and Flavia Fascendini
Graphic design
Monocromo
[email protected]
Phone: +598 2 400 1685
Commissioned by the Association for Progressive Communications (APC).
Conducted with support from the International Development Research
Centre (IDRC).
The views expressed in this publication are those of the individual
authors and not necessarily those of APC or IDRC.
A practical guide to sustainable IT
Published by the Association for Progressive Communications (APC) with
support from the International Development Research Centre (IDRC).
South Africa
2012
Creative Commons Attribution 3.0 Licence
<creativecommons.org/licenses/by-nc-nd/3.0/>
Some rights reserved.
APC-201206-SU-R-EN-DIGITAL-162
ISBN: 978-92-95096-71-4
Unit 11
renewable power
When you have taken all practical measures to adapt your equipment
and procedures to more efficient computing, there remains one external factor which can be improved: the power supply. Around two-fifths
of the carbon emissions produced each year are the result of electricity
generation.1 By comparison, transportation produces just over a fifth,
and industrial emissions are another fifth. Of the emissions from
power generation the majority are the result of coal burning – and coal
burning also creates problems due to the emission of acid gases, which
damage wildlife and crops, and polluting heavy metals. Two-thirds of
the world's power is generated from fossil fuels,2 and although de-carbonising power production will not, on its own, solve the problem of
climate change, it is an essential step in tackling the problem.
For most ICT users their source of power is most likely to be the electricity
grid. Just as recent operating systems have become inextricably linked to
the use of broadband data connections, much of our modern electronics
is tied to the 24-hour-a-day availability of a mains power supply – and in
many states there are few other options. In that respect, the modern electricity grid mirrors the global economic process generally; it is built upon an
underlying assumption that there will be a never-ending supply of energy
and resources in order to make society function. In contrast, users of offgrid power systems know that there are finite limits to their power supply;
and the scale and seasonal variation of off-grid power systems requires
that electricity use must be monitored and adapted if they are to have
power available when they need it.
How we use electrical power is influenced by the equipment we use,
but the source of power production has a significant effect on our ecological footprint. How you go about addressing this issue is dependent
1. International Energy Agency (2011). CO2 Emissions from Fuel Combustion. www.iea.org/co2highlights/co2highlights.pdf
2. International Energy Agency (2011). Key World Energy Statistics. www.iea.org/publications/freepublications/publication/key_world_energy_stats-1.pdf
upon the budget you have available to purchase alternatives to fossilfuelled grid power, and your technical capabilities to purchase and operate these alternatives.
In this section we'll look at three potential options for improving the
ecological impact of your power supply:
• Changing the contract or tariff paid to your electricity supplier in order to support lower carbon or renewable energy technologies – this
is the simplest option as it requires little change on the part of the
consumer;
• Installing a grid-connected renewable power generation system –
this is a more complex and expensive option than simply changing
electricity supplier; and
• Developing an off-grid power supply system – this a more technically challenging option, although in some parts of the world off-grid
power supplies are the only option to run ICT equipment.
4 / A practical guide to sustainable IT
11.1.improving the source of your electricity supply
T
he ability to vary the source of your electricity supply is dependent upon the level of
liberalisation of the power grid in your area. In
more developed states the supply of electricity
is carried out by private companies, either partly
or wholly regulated by government. As part of
this process consumers may have a choice of
different power suppliers, and each supplier will
have a range of electricity tariffs for different
types of electricity generating technologies. In
less developed states power generation comes
in a variety of forms, from wholly state controlled to wholly privatised. The general problem here is that there is often a restricted choice
of power sources available to purchase through
the grid.
Different power generation technologies can
be grouped according to how “green” they are
(see Box 11.1). While some forms of power are
obviously renewable other power sources are
less beneficial for the environment. For example,
municipal waste incineration can create electrical power, and it is often promoted as an environmentally advantageous technology, although
research suggests that waste incineration produces less power than the energy which could be
saved if that waste had been recycled,3 especially
paper4 and plastics. In the same way, the burning
of biomass (wood and plant matter) can be less
damaging to the environment, but if the land the
fuel was grown upon had previously been forest,
or agricultural land producing food crops, the impacts are not much better than using fossil fuels.
For this reason it is essential to consider what
3. GAIA (2007). Incinerators vs Zero Waste: Energy and the
Climate. www.no-burn.org/downloads/GAIA_Incinerators_vs_ZeroWaste.pdf
4.European Environment Agency (2006). Paper and cardboard - recovery or disposal?, EEA Technical report No
5/2006. www.eea.europa.eu/publications/technical_report_2006_5/at_download/file
power sources are used to create the electricity
that support our ICT needs. Rather than considering just the direct carbon emissions, it's important to use life-cycle analysis studies of power
production which take land use change and other
indirect effects into account5.
In states with a liberalised energy supply many
different producers supply the grid with power.
The power produced from these sources is then
balanced by the amount of power individual users buy from the grid. Therefore with a “green”
energy tariff, while you may not be physically using renewable-generated electricity, the amount
you consume will be balanced by the amount of
renewable power entering the grid. By contracting
with a provider of renewable electricity you can
purchase some or all of your electricity needs from
renewable sources. While the cost of a renewable
supply tariff is usually higher than the average
grid price, how “green” the sources are is often reflected in that price. Large-scale hydro and waste
incineration are often priced around the same rate
as fossil-fuelled electricity. The most sustainable
sources, such a geothermal, wind and solar power
are usually more expensive.
While not a solution for all the ills of the
modern world, buying renewable electricity is an
important step in moving society towards more
sustainable operation. Unless people are willing
to invest in non-fossil fuel electricity the alternatives required to address climate change will
not be created. If it is affordable, buying renewable electricity is a means to encourage investment in those alternative sources of energy.
5. Benjamin Sovacool (2008). Valuing the greenhouse gas
emissions from nuclear power: A critical survey, Energy
Policy, Vol.36 pp.2940-2953. www.nirs.org/climate/background/sovacool_nuclear_ghg.pdf The figures from this
paper are quoted for each energy source listed in Box 11.1.
Renewable power / 5
Box 11.1.
Impacts of electrical power generation technologies
The impacts of our electricity supply depend upon the
sources used to generate it. At present the global power
system is dominated by the use of fossil fuels renewable
power sources make-up less than a fifth of supply. The
list below outlines the impact of different energy sources, ordered from the highest to the lowest level of carbon emissions. The figures are the life-cycle emission of
carbon dioxide (in grams of carbon dioxide per kilowatthour, gCO2/kW-he) for a unit of electricity produced from
each source:
• Coal (960gCO2/kW-he) Coal is primarily used for power
generation around the world. There are different grades
of coal, and while high quality bituminous coal produces less carbon emissions, the use of lower quality brown
coal and lignite, or even peat, will produce more.
• Heavy oil (778gCO2/kW-he) Heavy oil is a low quality,
sticky, tarry form of oil and for that reason it is cheaper
than the price of oil quoted in the media. While its low
price makes it an alternative to coal for power production, it tends to produce more soot, acid gases and
heavy metal emissions than higher quality diesel fuel.
• Diesel (778gCO2/kW-he) Diesel is often used for power
generation as a back-up for the large power plants
which supply the grid. In states with a poor quality
power supply, diesel generators are often used as an
alternative during blackouts.
• Natural gas (443gCO2/kW-he) Natural gas is used primarily in more developed nations. As it is a higher quality
fuel it produces less emissions than other fossil fuels.
• Nuclear (66gCO2/kW-he) While there is much controversy over the use of nuclear power, it only makes up
13% of global power generation less than is produced
from large hydroelectric dams.
• Geothermal (38gCO2/kW-he) Geothermal power is
produced in volcanically active areas, such as Iceland,
the US or Kenya. It uses hot rocks to create steam to
generate power.
• Solar photovoltaic (32gCO2/kW-he) Photovoltaic (PV)
cells turn sunlight into electrical power. While the
greatest solar resource is in the tropics, even at higher
latitudes photovoltaic cells can still produce a viable
amount of power. Some manufacturers now produce
solar PV kits to power laptops and mobile phones.
• Biomass (14-35gCO2/kW-he) Biomass is plant matter.
It can be burnt in power stations in the place of coal,
or turned into liquid fuels such as biodiesel for use in
generating equipment.
• Solar thermal (13gCO2/kW-he) Solar thermal generation is used in desert regions, using mirrors to focus
solar heat and create high-pressure gas to turn powergenerating turbines.
• Small-scale hydroelectric (13gCO2/kW-he) Small-scale
hydro uses small flows of water in streams, sometimes without the use of a dam to trap water. As water is relatively heavy, micro-hydro is a good source of
power for off-grid electrical systems.
• Biogas/anaerobic digestion (11gCO2/kW-he) Biogas is
created by the digestion of animal manure and plant
matter by bacteria. It produces methane which can be
burnt in modified generators or gas engines to produce electricity.
• Onshore wind (10gCO2/kW-he) Onshore wind is one of
the fastest growing sources of renewable electricity.
While the largest turbines now produce up to five-million watts of power, small-scale turbines producing 75
to 150 watts can be used to power a laptop computer.
• Large-scale hydroelectric dams (10gCO2/kW-he) Large
hydroelectric dams which tap the power of the world's
largest river basins produce 16% of the worlds power.
While they produce low-carbon electricity, they are
highly damaging to build and often flood valuable agricultural land and wildlife habitats.
• Offshore wind (9gCO2/kW-he) Offshore wind is slightly more efficient than onshore wind because of the
higher and more consistent wind resource available
out at sea. Even so, it is more expensive because of
the problems of building and developing turbines at
sea.
6 / A practical guide to sustainable IT
11.2. grid-connected renewable power systems
A
nother way of using renewable electricity
is to generate your own from on-site renewable systems.6 This option depends upon
the suitability of the location to construct an
efficient renewable power system, and whether the electricity supplier/power grid operator
allows power to be fed back into the grid. Ideally the amount of generating capacity should
match the average amount of power consumed, although the cost, size and ability to
dump excess power back into the grid are all
factors in the planning and installation of gridconnected systems.
An important consideration in creating a
grid-connected power system is cost. While
developing a grid-connected renewable system is likely to be competitive with buying renewable electricity from the grid, it will never
be a means to reduce the cost of electricity
overall. That's because, even in those nations
where electricity is very expensive, the cost of
installing and maintaining small-scale gridconnected systems will be greater than the
large economies of scale offered by large power
grids. But, as noted above, if we wish to develop an alternative to the fossil-fuelled power
grid then it is small, local and largely self-contained systems such as this (collectively called
distributed generation)7 which will be required
to address our current demand for electricity.
Figure 11.1 shows a typical grid-connected
power system. Electricity produced by one
or more renewable generating technologies
is supplied to a synchronising inverter. This
converts the low voltage direct current (DC) of
small renewable technologies into high voltage alternating current (AC) used by the power
grid. This allows the locally generated power to
flow into the system without generating interference with the power from the grid.
If the renewable power sources do not generate enough current the grid supplies the difference between what is being generated and
6.For example, see Wikipedia: 'Grid-connected photovoltaic
power system'. en.wikipedia.org/wiki/Grid-connected_
photovoltaic_power_system
7. Wikipedia: 'Distributed generation'. en.wikipedia.org/wiki/
Distributed_generation
what is being used. Where the local system
produces more than required it is possible, if
the grid operator allows it, to feed that excess
power back into the grid. This is usually done
by having two electricity meters. One measures the power used from the grid, while the
other measures the power flowing back to the
grid. When the utility company sends the bill
they calculate the price of the power supplied
to the grid and subtract that from the price of
the power consumed (note, grid operators may
not pay the same amount for the power you
supply them as they charge for the power they
supply to you).
Over the last two decades grid-connected
renewable power systems have become popular in many states because they allow people
to produce their own energy8 without the problematic restrictions of being wholly cut off
from the grid. In some European states governments pay a premium for the power produced,9
and so the public can earn money from operating these systems in homes and businesses
(they have become especially popular on rural
farms where the large space available allows a
much larger scale of installation). One difficulty that has arisen with these systems is that
the synchronising inverter requires electricity
to function. If the generating system produces
insufficient power, or it's sited in a very poor
location, the system can actually consume
more electricity than it creates (this was a particular problem identified with small wind turbines designed for installation on rooftops in
the UK).10
The problem with grid-connected renewable systems is that many of them do not
function during a power cut. That's because
the synchronising inverter requires the signal
from the power grid to function – even if you
are generating power, it will not be supplied to
8.Wikipedia: 'Grid-connected photovoltaic power system'.
en.wikipedia.org/wiki/Grid-connected_photovoltaic_power_system
9.Wikipedia: 'Feed-in tariff'. en.wikipedia.org/wiki/Feedin_tariff
10.Encraft (2009). Warwick Wind Trials. www.warwickwindtrials.org.uk
Renewable power / 7
Box 11.2.
Uninterruptible power supplies
While not directly related to renewable energy, this is a
topic of relevance to the provision of power to computers.
Uninterruptible power supplies (UPS) are a means of
protecting equipment against power cuts. For servers
and small networks, especially when using a clientserver network, a UPS protects against the data loss
caused by small fluctuations or temporary interruption
of mains power. In the most developed states, where the
electricity grid has a very high reliability, UPSs are only used
in large data centres and corporate networks – where high
reliability is an essential part of the services provided. In
less developed states, where brown-outs and temporary
interruptions are more commonplace, the use of UPSs to
prevent data loss can be more common – although often
the costs of these units deters their wider use.
How expensive the UPS is depends upon how long
you want it to function. The cheapest only provide
a few minutes of power – just enough to enable the
server/desktop to close down the running programs
and prevent data loss, or to prevent small fluctuations
in the supply interrupting the computer. More expensive
systems use a large bank of batteries to provide power
for longer periods, or have a small battery bank to keep
the equipment running while a generator starts up to
supply power.
If data loss from an unreliable power supply is
a problem, using a UPS is often a good investment
because of the time and data saved. However, for most
small computer users having a UPS for a single desktop
machine can be expensive it is more practical to use a
laptop computer instead. The internal battery of the
laptop will cover temporary losses of power just like
a UPS, although you will have a problem if using other
mains-powered printers and peripherals. Using a laptop
is also better suited to off-grid power supplies, not only
because of their greater efficiency but also because
laptops run at low voltages which can be matched by
most small, renewable-power systems.
8 / A practical guide to sustainable IT
Figure 11.1.
Grid-connected power system
Solar
Wind
Hydro
Electricity
meter(s)
Power
grid
Building power
supply
incoming
outgoing
Synchronising
inverter
the building. To get around this problem some
systems incorporate battery storage, allowing
them to keep the inverter running without a grid
supply. In effect, they function like a large uninterruptible power supply for the whole building.
Due to their greater complexity, these systems
are more expensive to install and require more
maintenance. Even so, if the reliability of the
grid supply is an issue, grid-connected renewable generation can be a means of securing the
power supply to the building in the event of the
grid going down.
11.3. off-grid renewable power systems
A
n advantage of renewable power technology is that it allows the development of
power systems well beyond the reach of the
power grid.11 This has obvious benefits for developing nations, and also for the use of mobile systems (for example, built into vehicles
or vans) which allow ICTs to go on tour into
rural areas. The critical factor in the design of
an off-grid system is the average amount of
power that needs to be supplied, and how long
it must be supplied for. These two measures
determine the amount of equipment required
and thus the costs of the system.
Unlike the power grid, where more power
can be supplied instantaneously on demand,
11.Wikipedia: 'Off-the-grid'. en.wikipedia.org/wiki/Off-the-grid
the generating and storage capacity of an offgrid system has absolute limits to its use. In
order to make the costs and scale of the offgrid power supply manageable, the equipment
used must function as efficiently as possible.
The cost of supplying each additional kilowatt-hour of power is greater than for mainspowered equipment, and adding more power
generation or storage capacity to supply inefficient equipment represents an unnecessary
expense. As a result, the cost of more expensive but efficient computers and other equipment can often be justified by the cost savings
from the power saved.
Figure 11.2 shows a schematic of a typical off-grid power system. By examining this
you should be able to understand how these
Renewable power / 9
systems work. There are many companies
producing systems such as this, and they will
construct/install it in order to ensure its safe
operation in accordance with national building
and electrical codes. With a basic understanding of electronics, it's relatively simple to construct one from individual parts. Either way, in
order to specify the size and performance of
the installation it is necessary to have a basic
grasp of the principles involved.
At the heart of the system is the battery
storage.12 Its capacity determines how much
power the system can supply, and for how
long. It's also the most significant hazard in
the system. A battery is a reserve of potential
energy. When supplied at the required rate
that's quite safe, but if a major fault occurs
that potential energy can be released almost
instantaneously – creating both a fire and flash
burn hazard. Guarding against this is a matter
of system design, protecting against short circuits, power surges, etc; and mechanical good
design, ensuring that the battery is housed in
a suitable enclosure to protect it against physical damage, rain, frost, and heat.
Off-grid systems13 operate at low voltages
using direct current. A commercial system
might use 24 volts or 48 volts, whereas most
self-built systems will use 12 volts as this is
the standard used in leisure/off-grid consumer
systems. The voltage is a factor because it has
an effect on efficiency – the higher the voltage,
the more efficient the system. It is also important to consider the ease of maintaining and
repairing the system – 24 and 48-volt components are relatively harder to source than the
12-volt units available through many outdoors
and mobile home dealers.
There are a number of different battery
technologies available, each with different
costs and characteristics. The batteries used
in cars and lorries are of low quality, and while
they can be used to store power it's very inefficient to do so as they lose so much during
charging, and can only be discharged by a small
amount before cell damage occurs. Most batteries for power systems, while similar to automotive batteries, are more advanced “sealed”
lead-acid batteries. These have a longer life,
are more efficient to charge, and can use up
to half of their rated capacity before battery
damage occurs. There are a number of different types of deep-cycle battery, from the
basic leisure batteries used in mobile homes,
to more advanced industrial batteries used in
uninterruptible power supplies, to the highly
specialised gel batteries designed for use in solar PV systems. How well the system performs
over its lifetime depends to a large extent on
the type and quality of the battery technology
used.
Which power source is used to charge the battery will depend upon the feasibility of each technology for the application chosen. Some technologies are relatively mobile while others are only viable on a fixed site. Another factor is power density
– how much power can be produced with a given
amount of space and equipment:
• Solar photovoltaic14 (PV) panels are the simplest option. They're essentially a passive
technology – you put them in the sunshine
and they produce power.
• Wind power15 is the next most dense source
of energy. This is more complex to construct
as it requires a tower to be erected.
• Hydro power16 is the next most dense. The
difficulty is that this requires the installation
of pipework to tap a source of falling water
– the greater the height the water drops,
the greater the pressure in the pipe and the
higher the power output.
• It is possible to use a generator powered by
biofuel17 or biogas. This is a heavier and more
complex operation, but it represents a very
dense source of power as gas and biofuel
contain a lot of energy in a small volume of
fuel.
12.Wikipedia: 'Lead-acid battery'. en.wikipedia.org/wiki/
Lead-acid_battery
15.Wikipedia: 'Wind power'. en.wikipedia.org/wiki/Wind_
power
13.For a general introduction see the Homepower Magazine
website. homepower.com/basics/started/
16.Wikipedia: 'Microhydro'. en.wikipedia.org/wiki/Microhydro
The battery store has a fixed capacity. If the
battery was continually charged past that
point it would slowly degrade the battery, and
in the worst case could lead to a fire or release
of flammable gases. To protect against this
14.Wikipedia: 'Photovoltaic system'. en.wikipedia.org/wiki/
Photovoltaic_system
17.Wikipedia: 'Biofuel'. en.wikipedia.org/wiki/Biofuel
10 / A practical guide to sustainable IT
Figure 11.2.
A typical off-grid power system
fuses
Charge
controller
Voltmeter/battery
condition monitor
Solar
Battery
storage
Shunt
regulator
Low voltage
disconnect
Wind
Inverter
DC power
Hydro
Generator
AC mains
power
the battery must have a cut-out device which
prevents overcharging:
• Certain power sources, such as solar PV,
can be automatically disconnected to prevent overcharging. This is achieved with a
voltage-controlled switch called a charge
controller.18 When the battery reaches full
capacity its voltage begins to rise exponentially. As it rises above a set point the
controller disconnects the panels. More advanced controllers for larger PV systems
(half a kilowatt or greater) – called maximum
power point tracking controllers – sense the
optimum operating voltage of the solar panels and adjust according. This increases the
efficiency of the system by 15% in summer
and up to 30% in winter.
• Other power sources, especially wind and hydro, cannot be disconnected to prevent overcharging. For example, if you disconnected a
wind turbine the resistance to the wind created by the battery is removed and the turbine
would spin faster and faster until it ripped
itself apart. In these cases a shunt regulator
is used. Like a charge controller it senses the
battery voltage, but instead of disconnecting
it switches the current to a bank of high capacity resistors which dump the excess current as heat (in the most ecological designs,
the excess power might even be used to heat
water).
Note that many of the diesel/petrol generators19 designed for use with batteries include
over-charge controls as part of their design,
and will gradually slow the engine to an idle
tick-over once the battery is charged (more advanced models will automatically turn off and
on in response to the change in battery voltage). If using a very basic generator without
these advanced monitoring systems it should
be connected to the battery using a charge
controller. This will disconnect the load and the
generator engine should automatically slow
down to an idling tick-over.
At the simplest level, using the power
stored in the battery involves connecting a load
across the terminals. In practice it is more complex as you also need to monitor the battery
condition to prevent it being over-discharged.
18.Wikipedia: 'Charge controller'. en.wikipedia.org/wiki/
Charge_controller
19.Wikipedia: 'Engine generator'. en.wikipedia.org/wiki/
Engine-generator
Renewable power / 11
Just like over-charging, regularly exceeding the
battery's discharge limit will cause damage. Most
commercial off-grid systems have a single computerised controller. This monitors both the charging and discharge of the battery store, and gives
a read out of how much energy is stored inside
the battery. Self-built systems assembled from
individual parts usually have a separate battery
monitor – often no more than a voltmeter – and a
low voltage disconnect unit. Just like a charge controller, this monitors the battery voltage and in
the event it falls too far it disconnects the load
to prevent damage to the battery.
The power from the battery can be used directly if the equipment functions at that voltage. As noted above, it's essential to use a lowvoltage disconnect unit to protect the battery if
you use the power directly. For devices which do
not operate at the battery voltage you will need
either a power regulator to drop the voltage
down to the required level, or a power converter
(sometimes called a “DC to DC” or “buck converter”) to step-up the voltage to the required
level. For example, most small self-built systems operate at 12 volts but most laptops use
18 to 20 volts. There are a number of power converters available on the market. Often these are
designed for use in cars, and can be adapted to
work with small battery-powered supplies.
Finally the battery's DC voltage can be converted into mains AC using a power inverter.20 Some
very expensive inverters can take any input voltage, but most inverters are designed to be used
with a specific battery voltage either – 12, 24 or 48
volts. There are two general types of inverter:
• Modified sine wave inverters produce a very
rough approximation of mains voltage. This
means they are more efficient, but the modified sine wave can affect the operation of
voltage sensitive equipment such as TVs and
video recorders, data projectors and desktop
computers. Mains lighting and many types
of motor-driven equipment are usually unaffected.
• Sine wave inverters create a fully compatible
mains supply, although doing this can use
30% to 50% more energy than using a modified sine wave.
If you are only using an inverter, a low-voltage
disconnect is not usually required as most inverters include an automatic disconnect. However, when you buy the inverter you should always check the voltage at which the inverter's
disconnect functions to ensure that it doesn't
over-discharge the type of battery you are using.
For those without experience of electronics or mechanics all this may seem rather
daunting. Even so, if you were to buy a commercially produced system the considerations
and specifications that you need to answer
to make a purchase would cover much of this
same ground – although perhaps not in the detail explored here. Before moving on to build
or use a much larger system, you might find it
helpful to buy a small educational solar power
kit. These use exactly the same system components, albeit with a fraction of the power
capacity. This enables you to learn more about
the design and construction of these systems,
and to get a basic grounding in the principles
of their operation, before you move on to constructing more large-scale systems.
It should be noted that, even with the bestdesigned off-grid system, there may be times
when it simply runs out of power. That's the
nature of renewable energy; it is variable, and
occasional natural variation will challenge the
assumptions made in the design of most systems. On these occasions we just have to accept that we do no work – nature has given us a
holiday and we should do something else which
does not involve the consumption of electricity!
20.Wikipedia: 'Power inverter'. en.wikipedia.org/wiki/
Power_inverter
12 / A practical guide to sustainable IT
paul Mobbs
This practical guide to sustainable IT offers a detailed, hands-on introduction to
thinking about sustainable computing holistically; starting with the choices you
make when buying technology, the software and peripherals you use, through to
how you store and work with information, manage your security, save power, and
maintain and dispose of your old hardware. Suggestions and advice for policy makers
are also included, along with some practical tips for internet service providers.
Written by IT expert and environmentalist Paul Mobbs, the purpose of the guide is
to encourage ICT-for-development (ICTD) practitioners to begin using technology
in an environmentally sound way. But its usefulness extends beyond this to
everyday consumers of technology, whether in the home or office environment.
We can all play our part, and the practice of sustainable computing will go a long
way in helping to tackle the environmental crisis facing our planet.
A practical guide to sustainable IT A practical guide to sustainable IT
A practical guide
to sustainable IT
This is also more than just a “how to” guide. Mobbs brings his specific perspective
to the topic of sustainable IT, and the practical lessons learned here suggest a bigger
picture of how we, as humans, need to live and interact in order to secure our future.
The guide is divided into 12 sections (or “units”), with each unit building thematically
on the ones that have come before. They can be read consecutively, or separately.
The “unit” approach allows the sections to be updated over time, extracted for use
as resource guides in workshops, or shared easily with colleagues and friends.
The guide has been developed on behalf of the Association for Progressive
Communications (APC), with funding support from the International
Development Research Centre (www.idrc.ca). It is part of a APC’s GreeningIT
initiative, which looks to promote an environmental consciousness amongst
civil society groups using ICTs, and amongst the public generally. Other
publications and research reports completed as part of the GreeningIT initiative
can be downloaded at: greeningit.apc.org
Paul Mobbs
Tapa_a_practical_guide.indd 1
06/08/12 12:58
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