Lionel 6-85226

Depends on the specific products.  Many lamps are designed for 12-14 volts and will burn to hot and bright on 18 volts, they may also fail much sooner.  You need to be specific as to what lamps you're dealing with and if they're truly rated for 18 volts.

As for how many lamps it would support, that's also not possible to answer without knowing what lamps.  All lamps are not created equal, and they also don't have the same power requirements.

Powerhouse can supply 10amps at 18volts . Assume all 10 amps available for lamps. Reserve 1 amp for overhead (distribution losses, not running powerhouse at max output), leaving 9amps for lights.

Be aware that the output of the powerhouse is fixed at 18v, so LED current limiting resistors must be calculated based on 18VAC, and/or incandescent bulbs be rated for 18VAC

LEDs use 20 milliamps max, which is .02 amps, so doing the math of 9 / .02 = 450 LEDs. Remember LED spec of Volts and Amps are DC.

Lionel incandescent bulbs are in the 100 to 250 milliamp range, so using 200 milliamps ( .2 amps) the math is 9 / .2 = 45 bulbs.

Being somewhat conservative, but gives you a ballpark idea.

Note 1: When calculating LED current limiting resistor value, remember that 18VAC has a peak voltage of 25volts, and the current limiting resistor should be calculated for the this peak voltage to prevent overdriving amperage rating of the LED. Example, RED LED has voltage drop of 2.4VDC, and 20milliamps max. The current limiting resistor calculation would be 25.2 - 2.4 = 22.8, 22.8 / .02 = 1,140 ohms. 1,200 (1.2K) would be next standard resistor value.

Note 2: Sorry to add confusion, but if you really wanted to go crazy, and 450 LEDs isn't enough, you could put LEDs in series and greatly boost the number of LEDs you could have. Example: For the RED LED of 2.4 volts used in Note 1, you could easily put 6 in series, which would result in a total LED voltage drop of 6 x 2.4 = 14.4V. Current limiting resistor would be 25.2 - 14.4 = 10.8, 10.8 / .02 = 540 ohms. This series technique would result in 450 x 6 = 2700 LEDs. Have fun wiring this many LEDs!!!!!!!!!

Thanks for responding. The bulbs are in MTH buildings. There are anywhere from one to six bulbs in each building. The Lionel street lights that I have have one bulb. None of the lights are LED. I've been using a Lionel 6-32923 transformer but have never been comfortable with it. If neither of these is a good alternative, what do you suggest.

I'd probably consider picking up a postwar transformer, something like the KW is a good choice.  Add some decent circuit breakers to each of the two outputs and you can power a bunch of this stuff.  The bonus with the postwar transformer is you have variable voltage so you can tailor it to the requirements of the accessories and not be overdriving the bulbs.

I'd prefer to use new equipment if at all possible. The bulbs are 10 to 14 volts each. More thoughts on how to make this work are appreciated. I wish I understood electricity .

I currently use three 6-32923 to power accessories and two CW-80 to run two trains. Should I bite the bullet and buy a ZWL?

I would look into a computer power supply. For under $40 you can get 500 watts of 12 vdc power that will run a lot of lights. You can even share the layout ground to make wiring simpler.

Thanks for all of the suggestions. I appreciate them. I have one additional Lionel option I'll ask you about. It's Lionel 6-37947. Is this a viable option?

It would certainly work, but it's an expensive option, you can probably buy half a dozen postwar transformers for the price of one of those!  The cheapest I see them is $275, that's a lot of money for 180 watts!