Apparently Arial isn't a very efficient font, when it comes to ink consumption. This article claims Times New Roman is 27% more efficient.
Another article claims Garamond was the most efficient font of 10 that were tested, and appears to show Times New Roman in 4th place.
Neither of these articles seem to be particularly high quality science though. Is anyone aware of any work that compares ink consumption of fonts while still taking into account the readability?
I found (parts of) 2 studies but as far as I can tell neither included readability.
At the bottom of the first article you link to, they credit the original source and link to this Consumer Reports webpage. However that page was updated earlier this year and it seems the original report is not available anymore. Other sources (like this Dutch webpage from April 2016) quote what was probably in the original Consumer Reports report:
Times New Roman: 27% less ink usage compared to Arial Calibri: 23% less ink usage compared to Arial Century Gothic: 21% less ink usage compared to Arial Trebuchet MS: 10% less ink usage compared to Arial Tahoma: 5% more ink usage compared to Arial Franklin Gothic Medium: 7% more ink usage compared to Arial Verdana: 10% more ink usage compared to Arial
A commercial company called Ecofont (no affiliation) claims that
Independent tests from Buyerslab demonstrate savings up to 50% in toner ink with Ecofont compared to normal printing
so it seems this would outperform even Garamond. Ecofont adds tiny, invisible holes to an existing font such as Arial, Calibri, Tahoma, Times New Roman and Verdana thus reducing ink consumption. However the Buyerslab report doesn't mention anything about readability, plus the report was commissioned by Ecofont so it is questionable whether the research was really independent.
The latest version of the Consumers Report on Ways to save money on printer ink mentions a few other ink (and potentially environment saving) tips:
By leaving an inkjet printer on, you avoid triggering a maintenance cycle each time you use it. According to our test results, that can yield big savings from your ink costs because many of the printers we evaluated used as much ink to clean the print heads as they did for actual printing.
Of course you are trading electricity for ink here, so it's doubtful if this helps from an environment point of view.
... use the draft mode in your printer settings... This mode not only uses less ink but also allows you to print faster. Depending on the printer type, model, and manufacturer, it could be called Toner Save, EconoMode, or Draft Quality.
Be sure to strip needless ads and logos from a document before printing it, too.
It may be obvious, but alternatively to reduce your environmental impact you could:
I wish to look at this in terms of CO2 footprint, rather than ink consumption.
Some random source on the internet suggests that the CO2 footprint of a toner cartridge is around 5Kg for a new cartridge or 2Kg for a refilled one.
The laser printer in my office gets around 31,000 pages at 6% coverage, or around 2,000 pages 100% coverage. Arguably with 30% coverage of full page text you can get 6,000 pages per cartridge.
With these figures we can estimate that the CO2 footprint for the ink consumption is between 0.16g to 0.83g per page.
The CO2 footprint to manufacture one piece of A4 printer paper is 4.17g. So the ink represents between 3% to 17% of the CO2 footprint from printing.
You might be able to optimise ink consumption, and find the most readable font that uses the least ink but its only going to have a negligible effect on the environmental impact of printing.
If you really need to read something, then keep it on a screen, reduce ink consumption by not printing.
If you really do need to print something, like if your life depends on it, than choose a font that looks nice and will have the most impact to the person who is holding the sheet of paper, rather than agonising over a small fraction of resource consumption.
