LED lights - how to buy, which to buy?


Hi! I need to reduce 12V power consumption. I want to install LED bulbs for everything.
What is the power needed? I see H4 bulbs 3-8 watt with no radiator and I see 20-30 with radiator and a fan installed. What is the needed wattage for the same amount of light? Same question for W5W bulbs and turn sign ones. Thanx.


Regarding the headlight bulbs, I purchased something like these a while back: https://www.amazon.de/YuCarAc-Xenon-8000LM-Ersatz-Automodell/dp/B07TJWFX8K/ref=mp_s_a_1_6?keywords=led+h4&qid=1566487078&s=gateway&sr=8-6

But I must say, of the 2-3 LED bulbs I tested in the headlights, NONE of them worked well. The color was cool, and they were brighter for ME. But the optics of these lamps are simply not the same as the halogen bulb and therefore the reflector doesn’t focus the light correctly. In general, most LED headlight replacements create a lot of glare for other drivers.

I also purchased these for the license plate, which work great! Pay the extra money for PHILIPS. The Chinese brands break and flicker.

For the rear brake lights… no one has yet found a way to put LEDs here without getting all sorts of warnings on the dash. But there is a recent thread going on with some developments.