How Many Tonnes of CO2 in a ....? And How Much is it Worth?

CO2 value and content? 

Short article in Dec 14, 2013 Economist p70. Easy to miss.
http://www.economist.com/news/business/21591601-some-firms-are-preparing-carbon-price-would-make-big-difference-carbon-copy

http://en.wikipedia.org/wiki/European_Union_Emission_Trading_Scheme
ETS price $5 - "EUA" (which appears to be a tonne of CO2 'equivalents')
http://www.pointcarbon.com/news/euets/
http://en.wikipedia.org/wiki/Carbon_credit
California price - very roughly $12.

But for businesses internally: $6 to $60.
Non-energy companies around $10.
Energy companies around $30-40.

So how much CO2 in, say, a barrel of oil?

0.43 equiv-tonne CO2/barrel.

EPA: http://www.epa.gov/cleanenergy/energy-resources/refs.html

Comprehensive, yet simple open book calcs.

Given carbon credit (tonne of CO2, ETS EUA, etc.) prices above; what fraction of an energy unit cost is this cost/price?

http://www.oil-price.net/ Barrel of oil Jan 2014 about $100.
0.43 equiv-tonne CO2/barrel @ $10-40/equiv-tonne CO2 implies $5-20/barrel carbon price… five to twenty percent of oil price. Not insignificant, but not so high as to set off reality alarms.

"Theoretical" societal CO2 cost of $33/tonne implies $15/barrel.

http://www.epa.gov/climatechange/EPAactivities/economics/scc.html (using %3 rate at 2013?)

How much does it cost to produce a barrel of oil?

EIA: http://www.eia.gov/tools/faqs/faq.cfm?id=367&t=6

[And this excludes transportation and such.]  Very roughly $30/barrel.

Observations for rules of thumb:

“Market” cost divided by two gives roughly sum of production, societal and transport.

Production cost divided by two gives roughly societal cost.