What takes more energy: Drying your hands with a paper towel, or an
electric blower? Which is a "cleaner" source of energy?

hi mlentropy

In terms of ongoing cost air drying is better than paper towel, see
http://www.buildinggreen.com/auth/image.cfm?imageName=images/1101/energyuse.jpg&fileName=110106a.xml

however this calculation does not include the burden of manufacture
and disposal of the dryer, nor the disposal of paper waste

Nor does it take into account that they perform different tasks

Airdriers have been found to be colonies and distributers of bacteria
- and they are lousy at hand drying

@ Airdriers have been found to be colonies and distributers of bacteria

I do not think the balance of evidence supports this.

Studies pro-air or eqivalent for both methods, problems with paper:

Effects of 4 hand-drying methods for removing bacteria from washed
hands: a randomized trial.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10907386

Efficiency of hand drying for removing bacteria from washed hands:
comparison of paper towel drying with warm air drying.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15796287

Bacterial transfer and cross-contamination potential associated with
paper-towel dispensing.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=14639433

A microbiological evaluation of warm air hand driers with respect to
hand hygiene and the washroom environment.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11123464

Comparative effectiveness of hand-cleansing agents for removing
methicillin-resistant Staphylococcus aureus from experimentally
contaminated fingertips.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=7985822

Hot air electric hand driers compared with paper towels for potential
spread of airborne bacteria.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=2880906

Studies pro-paper:

Dispersal of bacteria by an electric air hand dryer.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=2698982

These are "neutral" medical studies. You can find plenty of other
reports on the Internet and elsewhere concluding either way sponsored
by companies on one side or the other.
I am always happy to invest the extra 20 seconds to dry my hands
properly if the method is air. From personal observation the majority
of people do not either wash or dry optimally, irrespective of method.

I'll certainly agree with your last statement !