For context, critics assume the following:
1. Identify the electricity grid mix for each mining jurisdiction
2. Apply the water impact of each energy source (eg nuclear, hydro)
3. Apply 👆🏼 proportionally to how much ⚡️ bitcoin consumes
4. Estimate a per tx water use
Let's examine why their assumptions are problematic...
1. Direct vs indirect water use
The biggest issue is they assume direct water use by miners when it's indirect (ie electricity generator water use). This is an important distinction so let's look at an analogy:
When we look at carbon, we estimate direct (scope 1) & indirect (scope 2 & 3) CO2 emissions. Steel, cement, pulp mills report direct carbon emissions under cap & trade. The ⚡️ generator does too so there's no double counting. But mining critics attribute power emissions to miners!
It's the same wrt direct vs indirect water use: think farms, pulp mills, textile mills using water directly, vs power plants that make the power they use
A miner w/ *direct* water use would employ:
- Evaporative cooling
- Hydro cooling
Thus 👆🏼 direct use is what the critics should estimate (note, these water cooling methods are not prevalent vs air cooled or immersion)
The water use from a power plant powering miners is not the same as the water used directly at a mining facility, in the same way that the water used by a Nestle bottle plant does not have the same indirect water impact from Nestles electrical consumption!
2. Inaccurate grid & country mix
Water critics assume miners are representative of the grid mix in their jurisdiction. But we know miners employ energy strategies to lower power costs - ie many projects co-locate w/ renewables or use stranded power. Further, the country mining stats critics use are out of date. Mining is extremely mobile & China & Kazakhstan play a much lower role than before.
Read more in the recent study from mining experts: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4634256
ALSO, let's say critics stick to ⚡️related water use. If they were fair, they'd consider the water use that's OFFSET from heat recovery applications in district, industrial & farm heating bc the heat energy offset would have had a water impact too! But they don't
3. Per transaction water use
Water critics assume the same fallacy when they say 1 tx uses the equiv amount of energy as a swimming pool, as when they assume 1 tx consumes a month's worth of household electricity use. "Per tx" is the wrong model & industry experts wrote great rebuttals wrt energy that are applicable to water:
1. https://www.coindesk.com/business/2021/03/05/the-frustrating-maddening-all-consuming-bitcoin-energy-debate/
2. https://bitcoinmagazine.com/business/bitcoin-energy-per-transaction-metric-is-misleading
Overall, critics aren't playing fair w/ the numbers & their math is off. A final thought to leave you with: Bitcoin miner heat recovery desalination projects are feasible - what will water critics say when they go live?
