Easy. Street lights are, by definition on all night. Sure, some cities may cut back to every second light, or so in the wee hours of the night but that is really an exception.
Now make this little calculation. The globe makes one complete turn every 24 h. Summer days are longer than winter days, but the two main seasons are of equal length, changing places every 6 months. A year is 12 months.
Summary: Every single spot on earth from the equator to both poles receive EXACTLY the same sunshine hours every year. There are 24 * 365 hours in a year, 8760 h for simplicity's sake
Answer to your calculation: XX number of street lights using yy kWh per hour are on 1/2 * 8760 hours every 12 months and consuming XX * YY * 8760/2
You may want to give some allowance for dawn and dusk minutes, deduct 2 * 10 min for those times every day.
Note your spelling. Kilowatts are abbreviated k (for kilo) W for Watts h (for hour) Write kWh
Technical abbreviations DO NOT have any plural "s" - so the common expression "mins" is totally offending to any one with a technical education. Minutes are abbreviated "min", just like hours are abbreviate "h"
Power plant design Engineer.
· 6 years ago