I looked up the brightness of leds comparatively. Looks like 20 lumens led is equivalent to a 4 watt night light?
•A 100 watt Bulb is rated at approximately 1700 lumens
•A 60 watt incandescent bulb is rated at approximately 800 lumens
•A 40 watt bulb is rated at 400 lumens
•A 4 watt night light bulb is rated at 20 lumens
This low efficiency device puts out 5 lumens per watt. There are LED bulbs (equivalent to 100 W incandescents) available that put out 50 to 100 lumens per watt, much more than incandescents and similar to CFLs. Of course, they cost a lot right now but they are rated at 40,000 hours lifetime. That's about 15 years of 8-hour days.