Are all alternatives equal?

I live in a quaint jurisdiction of Australia. We have a container deposit recycling scheme and a ban on the use of lightweight plastic bags. Practically that means two things;
(i) you NEVER see a recyclable container lying around as litter because an enterprising collector will have swooped it up and cashed it in, resulting in up to 85% of all eligible containers being recycled AND
(ii) everyone has to bring their own bags to the shops or purchase an alternative to non lightweight plastic.

The shopping bag discussion is worth having. The number of single plastic bag uses has fallen considerably since the introduction of the ban in May 2009. Research findings six months after the introduction found significant changes in behaviour and overall support in the community.

However are all alternatives to single use lightweight plastic bags equally better for the environment?

I was given this link as part of a Lifecycle analysis discussion recently at Uni which got me thinking. It is an old report now (December 2002) on the Environmental impact of plastic bags. On pages 36 and 37 there is a discussion about alternative bags and estimates of both carbon dioxide emissions and embodied energy. It is interesting to note the high impact of paper bags (associated with the processing requirements) and the much lower impact of reusable plastic boxes and the "green bag". The swag style is that associated with Ikea - much larger than the average shopping bag and not always suitable for lugging home the groceries.

Some food for thought this week...