[ivraatiems]

It just isn't really a measurable impact against an overall picture.

At maximum, a T580 can draw 44 watts. 8 hours per day, 365 days a year, at 50 cents a kWh (quite expensive for the US), that's $65 a year. That's a several-year-old computer already.

The W520 can draw a much higher (but still low relative to a desktop) 150 watts. The cost per year to run it would then be around $220/year - but again, that's assuming maximum power draw for much of the day every day. Your home refrigerator uses more than twice that.

For most people, I don't see this cost increase as a problem.

[0xbadcafebee]

For me power draw is about battery life. If you occasionally need to work without a power plug, or carrying your laptop from meeting to meeting all over the office, you really appreciate when the power lasts all day. My T14s battery draw of ~6.5W on the 57Wh battery will last me ~8 hours, good enough for a day unplugged at the office. (I'd love a bigger battery, but it is what it is...)

[ninalanyon]

My refrigerator doesn't use anything like 300 W average. An IKEA 310 l fridge is rated at less than 100 kWh per year.

Even if you add a 210 l upright freezer to it is is still less than 300 kWh per year. That's 300 kWh / (365 * 24 h) = 34 W