The powerplugs and outlets in Switzerland differ from those in EU countries and the US. You should bring a 230V AC power adapter in order to power/charge your devices. If you need to plug in many devices, also bring a multi-tap. You can buy adapters in Bern, but given the high prices in Switzerland, it's advisable to purchase your gear before coming to the conference.
For specific information about the power outlets available in Switzerland, refer to:
There are two types of plugs: