Interesting if you're hosting at home - ok I should perhaps narrow it down further to hosting at home in the UK - and were considering power factor correction capacitors to knock down the electricity costs:
"In a domestic single phase power supply, unlike commerce and industry, you do not pay reactive power charges and you do not have a kVA limit so the only one who would benefit from fitting Power Factor Correction would be the supply company since they would need to supply less "kVA" for a given killowatt consumption.
kW = kVA x pf.
Killowatts are killowatts and the simplest way to save them is to turn things off.
If your machinery is using motors, you may find reducing the voltage to these will save energy especially if they are not fully loaded.
I hope this helps.
Regards"