Reaching for a cable costs a second more and would save around 10000 tons of coal per year (based on your calculation) if the equivalent of coal power plants were reduced by the same amount.
You can’t have it both ways. If you’re counting the energy consumption of 8.3 billion people consuming 15 Wh, 365 times, then you’re also talking about “a second” for each, or 3 trillion seconds, or 95,000 years of time saved in exchange for that coal.
The difference is, that one second is personal cost. The CO2 is socialized cost. If you have a different perspective on this, I understand. When I looked up wireless charging because it looked cool and saw the numbers, I decided to stick with cables and not buy any wireless charging hardware.
And I’m saying that this particular issue is completely inconsequential. Based on worst case scenario assumptions (fully discharging a 15 Wh battery down to 0% every day, waste heat equal to 100% of the charge, all electricity from coal), you’re only using a 5.4 kWh per year, or about 2.5 kg of coal, about 4.6 kg of CO2 emissions.
That’s about 170g/6 oz of beef (27 kg CO2/kg beef). Commit to eating (or wasting) one less burger per year and you’ve made up for the worst case scenario, calculated using unrealistically large assumptions.
Or that’s 1.9 L/0.5 gallon of gasoline. Drive 25 km/15 miles less per year.
More realistically, we’re probably talking 80% charge per night, 80% efficiency, and an electricity mix that generates the US average CO2 emissions of 0.384 kg/kWh. That cuts it down to 3 Wh/day, 1.1 kWh/year, and about 0.42 kg of CO2.
That’s 16g of beef, or 0.17 L of gasoline.
The real impact comes from changes around the bigger uses of energy. Focus on the things using many orders of magnitude more energy, within your control: transportation, climate control, food choices. Consumer electronics are less than a rounding error.
You can’t have it both ways. If you’re counting the energy consumption of 8.3 billion people consuming 15 Wh, 365 times, then you’re also talking about “a second” for each, or 3 trillion seconds, or 95,000 years of time saved in exchange for that coal.
The difference is, that one second is personal cost. The CO2 is socialized cost. If you have a different perspective on this, I understand. When I looked up wireless charging because it looked cool and saw the numbers, I decided to stick with cables and not buy any wireless charging hardware.
And I’m saying that this particular issue is completely inconsequential. Based on worst case scenario assumptions (fully discharging a 15 Wh battery down to 0% every day, waste heat equal to 100% of the charge, all electricity from coal), you’re only using a 5.4 kWh per year, or about 2.5 kg of coal, about 4.6 kg of CO2 emissions.
That’s about 170g/6 oz of beef (27 kg CO2/kg beef). Commit to eating (or wasting) one less burger per year and you’ve made up for the worst case scenario, calculated using unrealistically large assumptions.
Or that’s 1.9 L/0.5 gallon of gasoline. Drive 25 km/15 miles less per year.
More realistically, we’re probably talking 80% charge per night, 80% efficiency, and an electricity mix that generates the US average CO2 emissions of 0.384 kg/kWh. That cuts it down to 3 Wh/day, 1.1 kWh/year, and about 0.42 kg of CO2.
That’s 16g of beef, or 0.17 L of gasoline.
The real impact comes from changes around the bigger uses of energy. Focus on the things using many orders of magnitude more energy, within your control: transportation, climate control, food choices. Consumer electronics are less than a rounding error.