LED technology is already very advanced, but not yet advanced enough to replace floodlight halogen bulbs. Even if it were possible in the short term to place LEDs in the shape of a halogen rod in such a way that cooling and light emission are ensured, the luminous flux currently achievable is too low. At present, very good LEDs can achieve luminous flux values of approx. 60 lumens per watt. To replace a 300W halogen rod (approx. 5000 lumens), the comparable LED rod would theoretically have to deliver about 85W. However, the cooling effort required is already so complex at outputs around 8-10W LED that it is currently not technically possible. In addition, there is the all-around illumination provided by halogen rods, which is difficult to realize with LED. With LED, the luminous flux would have to be increased by about a factor of 10, but that is not physically possible. At about 110 lumens per watt, the physical limit is reached. This leaves only a completely different LED technology, which is already being developed. OLED is the magic word and will repeatedly bring us a transformation in lighting matters over the next 10-15 years. Currently, only a few light sources can be sensibly retrofitted from a technical standpoint. These include normal light bulbs up to max. 60W with the two screw base types E27 and E14. Some spots up to max. 50W can also be retrofitted. But it always depends on the individual case, because the designs with the large heat sinks sometimes appear very impractical, which also limits their use in terms of illumination. And ultimately, the price should also be taken into account, because technically good light sources are significantly more expensive than what lies in bargain bins in many stores. Generally speaking, good LEDs are about a factor of 10 more expensive than the comparable standard light source. This also limits their use, because it results in a minimum operating time of approx. 3-4 hours per day in order to save money in a meaningful way. Energy saving at any price is possible, but no one will do it.