The article claims that they save 2.1 MWh per week (109 MWh per year) with a payback period of 4.5 years in Norway. It doesn't say how much it costs, but Norwegian electricity prices are around 83 EUR/MWh, so we can estimate that the lighting system costs roughly EUR 40k (US$43k).
Wholesale grid prices in the US are around ~$252/MWh at peak, which means the payback period in the US is only 1.5 years give or take, which is not a bad investment.
In the US freeways are not illuminated except near cities.
The headlights of your car are expected to be able to illuminate road signs.
This leads to design differences with US vs European headlights, with the US headlights aimed higher.
The next time you see a European car with fancy advanced headlights and wonder why you can't have that in the US realize it's because in Europe they illuminate road signs.
>The five-mile stretch of energy-saving street lights saves 2,100 kWH per week, which would amount to approximately 21 hours of ironing, or four hours of watching TV on a plasma screen.
Am I missing something? Five mile stretch? 21 hours of ironing? What iron is that.
I think they did their math wrong. If we assume an iron operates at 1000 W (probably about right), then 21 hours of ironing is 21000 Wh, or 21 kWh. Someone probably got a little confused and ended up off by a couple orders of magnitude.
I wonder how applicable it is to the US - most of the roads I know of with light traffic are also not lit. Maybe in some suburban streets or something.
Wholesale grid prices in the US are around ~$252/MWh at peak, which means the payback period in the US is only 1.5 years give or take, which is not a bad investment.
https://www.eia.gov/electricity/monthly/update/wholesale-mar...