Green Computing
Why computer energy is often wasteful
leaving the computer on when not in use (CPU and fan consume power, screen savers consume power)
printing is often wasteful
how many of you print out your emails or meeting agendas
printing out partial drafts
for a “paperless” society, we tend to use more paper today than before computer-prevalence
pollution
manufacturing techniques
packaging
disposal of computers and components
toxicity
as we will see, there are toxic chemicals used in the manufacturing of computers and components which can enter the food chain and water!
Energy Use of PCs
CPU uses 120 Watts
CRT uses 150 Watts
8 hours of usage, 5 days a week = 562 KWatts
if the computer is left on all the time without proper power saver modes, this can lead to 1,600 KWatts
for a large institution, say a university of 40,000 students and faculty, the power bill for just computers can come to $2 million / year
Energy use comes from
electrical current to run the CPU, motherboard, memory
running the fan and spinning the disk(s)
monitor (CRTs consume more power than any other computer component)
printers
Reducing Energy Consumption
Turn off the computer when not in use, even if just for an hour
Turn off the monitor when not in use (as opposed to running a screen saver)
Use power saver mode
in power saver mode, the top item is not necessary, but screen savers use as much electricity as any normal processing, and the screen saver is not necessary on a flat panel display
Use hardware/software with the Energy Star label
Energy Star is a “seal of approval” by the Energy Star organization of the government (the EPA)
Don’t print unless necessary and you are ready
Use LCDs instead of CRTs as they are more power efficient
Chemical Elements Used: Lead
used in soldering of printed circuit boards and other components
also used in glass for CRTs
It is estimated that between 1997 and 2004, 1.2 billion tons of lead was used in computer components
The problem:
lead can cause damage to the central and peripheral nervous systems, blood system, kidneys, endocrine system and cause negative effects on child brain development
lead accumulates in the environment and has toxic effects on plants, animals and microorganisms
electronics contribute 40% of the total amount of lead found in landfills and can make its way from landfills into the water supplies
Chemical Elements Used: Mercury
Mercury is used in
batteries, switches, housing, printed circuit boards
mercury is found in medical equipment, data transmission equipment, telecommunications equipment and cell phones as well
if is estimated that 22% of the yearly use of mercury is in electrical and electronic equipment
although a small amount of mercury is used, it is used in nearly all computer construction amounting to 400,000 pounds of mercury used between 1997 and 2004
The problem
mercury spreads out in water transforming into methylated mercury which easily accumulates in living organisms
it enters the food chain through fish that swim in polluted waters
methylated mercury can cause chronic brain damage
Other Chemical Elements
Cadmium is used in resistors for chips, infrared detectors and in semiconductors (plus older CRTs)
estimated that between 1997 and 2004, 2 million pounds of cadmium was used in computer components
The problem:
cadmium is classified as toxic, these compounds accumulate in the human body, particularly the kidneys
cadmium is absorbed through respiration and also food intake
cadmium has a half life of 30 years so that cadmium can poison a human body slowly through the human’s life
Hexavalent Chromium (Chromium VI) is used to treat steel plates (an anti-corrosive) and it is estimated that between 1997 and 2004, 1.2 million pounds were used in computer components
if you’ve seen Erin Brokovich, you know that this can lead to cancer and a number of other medical problems
Plastics
Plastics are found throughout the computer, largely from casings but also internally to hold components together
4 billion pounds of plastic were used to build computers and components between 1997 and 2004
One specific form of plastics used is polyvinyl chloride (PVC) which is used in cabling and housings
PVC is difficult to recycle and the production and burning of PVC generates dioxins and furans
The plastics in computers are often treated with flame retardant chemicals, particularly brominated flame retardant
these chemicals can act as endocrine disrupters and increase risk of several forms of cancer
they have been found entering the food chain
Chemical Elements Found in Computers and Components
Elements in bulk: lead, tin, copper, silicon, carbon, iron and aluminum
Elements in small amounts: cadmium and mercury
Elements in trace amounts:
germanium, gallium, barium, nickel, tantalum, indium, vanadium, terbium, beryllium, gold, europium, titanium, ruthenium, cobalt, palladium, manganese, silver, antimony, bismuth, selenium, niobium, yttrium, rhodium, platinum, arsenic, lithium, boron, americium
List of examples of devices containing these elements
almost all electronics contain lead & tin (as solder) and copper (as wire & PCB tracks), though the use of lead-free solder is now spreading rapidly
lead: solder, CRT monitors (Lead in glass), Lead-acid battery
List Continued
List of examples of devices containing these elements
tin: solder
copper: copper wire, printed circuit board tracks
aluminum: nearly all electronic goods using more than a few watts of power
iron: steel chassis, cases & fixings
silicon: glass, transistors, ICs, Printed circuit boards.
nickel & cadmium: nickel-cadmium rechargeable batteries
lithium: lithium-ion battery
zinc: plating for steel parts
gold: connector plating, primarily in computer equipment
mercury: fluorescent tubes (numerous applications), tilt switches (pinball games, mechanical doorbells)
sulphur: lead-acid battery
carbon: steel, plastics, resistors
Disposal
Consider that the average computer lifespan is about 2 years (cell phones < 2 years)
10 years ago, the lifespan of a computer was 5 years
between 1997 and 2004, it is estimated that 315 million computers became obsolete (and were discarded, donated, or recycled)
183 million computers were sold in 2004 (674 million cell phones!)
New users in China (178 million by 2010) and India (80 million by 2010) will require the creation of new computers
Disposal of these devices constituted 20-50 million tons per year (about 5% of the total waste of the planet)
this waste is called e-waste
where are we going to put all of it?
Other Solutions
Reuse: donate your computer components to people who may not have or have lesser quality computers
inner city schools, churches, libraries, third world countries
this however leads to the older computers being dumped but there is probably no way around this as eventually the older computers would be discarded anyway
Refurbish: rather than discarding your computer when the next generation is released, just get a new CPU and memory chips – upgrade rather than replace
while you will still be discarded some components, you will retain most of the computer system (e.g., monitor, the system unit housing, cables)
Are there adequate incentives to do either of the above? Do computer companies encourage refurbishing/upgrading?