[LINK] Greenhouse contribution of letters

[Tom Worthington]

At 06:26 AM 1/04/2008, Stephen Wilson wrote:
>Has anyone seen any analysis of the contribution to greenhouse of 
>paper letters ...

The US Postal Service is studying the contribution of letters to CO2 
emissions <http://www.usps.com/environment/greenhousegas.htm#H5>. But 
then they claim that advertising mail reduces harmful emissions, by 
informing consumers and so reducing shopping trips. So I am not sure 
how credible the research they fund is.

By my own back of the (recycled) envelope calculations, an airmail 
letter from Canberra to Brisbane produces about 136 g of CO2 
equivalent and this is one hundred times as much as email.

Here is the calculation, with more at 
<http://www.tomw.net.au/blog/2008/04/greenhouse-gas-from-paper-versus.html>:

A sheet of A4 paper weighs about 5 g 
<http://ansuz.sooke.bc.ca/professional/reference/paperweight.php>.

An envelope and stamp will weight about 7 g.

This gives a total of 12 g for a letter.

For a flight of around 2500km, 0.1260 kg per km of CO2 is produced to 
transport a passenger 
<http://climate-wise.com/calc/fnpw005/active/content/Emision_calc.htm>.

The standard weight for a passenger is 77 kg 
<http://www.caa.govt.nz/publicinfo/media-rel-weight_survey.htm>.

So that works out to about 1.64 g of CO2 per km per kg of cargo, or 
0.14 g per letter per km.

A letter which went 1,000 km (about the distance from Canberra to 
Brisbane) would produce about 136 g of CO2 equivalent.

>And what might be the marginal greenhouse improvement of using e-mail instead?

My estimate is that a 20 kbyte e-mail message (one A4 page 
equivalent) produces one gram of CO2 per year 
<http://www.tomw.net.au/blog/2007/10/one-gram-per-message-program.html>.

So email would be much better, as long as you did not keep the 
message online too long.

However, if the letter was only being transported a few tens of km 
within the same city by road, then the CO2 emissions for the paper 
letter would drop to under one gram. This would then might be more 
than an email message kept online a long time.

Obviously it is possible to reduce the impact of long distance paper 
mail by transporting it most of the way electronically and printing 
it near its destination. About twenty years ago I helped interface a 
system at the Department of Education to Australia Posts' system to 
do this. Setting it up was complex, but it worked reasonably well. 
This should now be easy to do with standardized Internet based protocols.

Australia Post have a service called eLetter, which seems to be for 
printing and delivery of mail. Unfortunately Australia Post seems 
have a very poor quality web site, making it difficult to find out 
about the service < http://www.eletter.com.au/>.

Also they seem to be concentrating on helping send more junk mail, 
with services such as Easy Post: <http://www.ausposteasymail.com.au>.

Large mail users, such as the federal government could send 
correspondence to the nearest capital city electronically for local 
delivery. Apart from saving greenhouse gases, this would save money. 
Setting up a system for the whole of the Australia Government would 
be no harder than the system I helped build for one agency twenty years ago.



Tom Worthington FACS HLM tom.worthington at tomw.net.au Ph: 0419 496150
Director, Tomw Communications Pty Ltd            ABN: 17 088 714 309
PO Box 13, Belconnen ACT 2617                      http://www.tomw.net.au/
Adjunct Senior Lecturer, ANU