Lamp A Lamp B
Enter here the Watt of two different lamps;
Watt is also know as Joule per second 1W = J/s
Enter the number of lamps you need in your project; number of lamps pieces
The Average Rated Life (ARL) is how long it takes for half the light bulbs in a test batch to fail. It's also been called a half-life. For example if 100 bulbs are tested and have an ARL of 1000 hours, 50 of the bulbs had died when the test time reached 1000 hours. average rated life h
Enter here the price in €uro of Lamp A and B; cost of one lamp
Additional costs can be wires, materials or control gears you need to buy in order to switch to Lamp B. The amount is seen as an investment, which will pay off over the time. additional cost
= enter here the price you pay for a kWh
            0.208 €/kWh = EU (28) for households
            0.120 €/kWh = EU (28) for industry
use a point . for comma!
average electricity cost
= time span that the lamps are turned on per year;
              1000 hours per year = households
              2580 hours per year = offices
              2900 hours per year = hotels
              168 hours = 1 week
              730 hours = 1 month
              8760 hours = 1 year
yearly operating time
= CO2 emitted per kWh of electricity generated. Those values do not just depend on the conversion technology, but also on factors such as location, thus giving rise to some variation.The electricity emission factor is the weighted average emission for a particular supplier (utility company) or country, taking into account the fuel / technology mix that is employed to generate the electricity.          use a point . for comma!
              0.197 kg/kWh Austria
              0.476 kg/kWh UK
              0.541 kg/kWh Germany
              0.083 kg/kWh France
              0.148 kg/kWh Peru
              1.005 kg/kWh India
CO2 factor
Amount of money to change from lamp A to lamp B. cost to replace lamp A
Point expressed in years, when the initial investment is paid off. break even point a
It is in fact the kilowatt hours saved per year. kWh saved kWh/a
The amount of CO2 that is not emitted per year CO2 saved kg/a
An approximation of the lamp's life time in years. lifetime in years a
Expenditures per year. It is actually a fraction of the lamps cost over the lifetime. lamp cost per year €/a
Kilowatt hours all lamps used over the project's time. kWh used per year kWh/a
The amount of money paid for running the lighting system. This is the crucial output why lamp B is more economic than lamp A. operation cost €/a
Costs that have to be paid for lamp A or lamp B over the whole timespan of the project. total cost per year €/a