I'll use that much energy by performing a google search for the answer, and then offset my carbon footprint by performing some extremely accurate mathematical calculations using ancient Babylonian clay tablets, instead of depending on gold:
https://www.google.nl/search?q=how+much+energy+is+used+by+go...
According to a 2009 post by Google: Together with other work performed before your search even starts (such as building the search index) this amounts to 0.0003 kWh of energy per search, or 1 kJ.
How much energy is required for one Google search? - Quora
https://www.quora.com/How-much-energy-is-required-for-one-Go...
Compared to:
https://www.google.nl/search?q=how+much+energy+does+an+ameri...
How much electricity does an American home use? In 2015, the average annual electricity consumption for a U.S. residential utility customer was 10,812 kilowatthours (kWh), an average of 901 kWh per month. Oct 18, 2016
How much electricity does an American home use? - FAQ - U.S. ... - EIA
https://www.eia.gov/tools/faqs/faq.php?id=97&t=3
So if "Electricity consumed per [Bitcoin] transaction (KWh)" is 173.00 kwh, and one Google search consumes 0.0003 kwh, then you can perform 173.00 / 0.0003 = 576,666.67 google searches (over half a million) per Bitcoin transaction.
If a house used 10812 / 365 = 29.62 kwh per day, then you can perform 29.62 / 0.0003 = 98,733.33 Google searches with the energy it takes to power a house for a day, or power the house for (24 * 60 * 60) / ((10812.0 / 365) / 0.0003) = 0.875 seconds with one Google search, if these gold-free clay tablets are as accurate as news reports say they are.