The issue of power cuts & fibre was raised recently at the Ultra Fast Broadband Dialogue Consultation. The current UFB plan is to not provide a Uninterrupted Power Supply with the installation, leaving it to the customer to decide whether or not they require backup in the event of a power outage and to incur any associated costs. The reason behind that decision was ; even if the UFB service was installed with a UPS most modern phones require power to operate, therefore UPS needs will depend on the requirements of the customer.
To put this into perspective with the current Fibre to the Home product, installs are provided with a UPS but it only covers the ONT*. This means the WRP400 or Phone & Internet box is without power and all services fail during a power cut. If you are technically inclined it’s possible to connect a Laptop to the ONT* and connect via PPPoE, giving you internet service. However this still leaves you without a phone and isn’t suitable for most customers.
Hopefully the above gives you some insight on the current situation, given the importance of emergency calling it could very well change at some point - an Uninterrupted Power Supply which covers both the ONT, Phone & Internet services may even become an integral part of the installation.
*ONT stands for Optical Network Terminal, the ONT converts the fibre optic light signals to electric signals which your router can then understand. It’s basically a signal translation unit for all the services (e.g.. internet, voice and video) which may be delivered to your Fibre enabled home.