Cost and practicality seem to always be an issue for most of us. Not enough money, site options.... As I do not have that concern / on well water, I never delved into it but UV was what I had understood to be good. If power is a concern, what if you did use UV for everyday use and had a good quantity stored for times that AC power is down? Also, If municipal water is running, then one will likely have power, be it intermittent throughout the day or perhaps only every three... days.

Then there are the solar panel options to recharge batteries. Either way, you are protected with your backup supply of water and the ability to replenish clean drinking water every time the power comes back on for a few hours or there is enough sun to recharge battery bank. But let’s face it, if power is down for longer then your backup supply lasts, city power is down or not enough days in the week to recharge batteries, one is best to hit the backup site.

Separating your drinking water from toilet water to reduce quantity of what needs to be treated is another possible option when working with limited power for UV filtration

Or invest in a good bank of batteries and use for UV as well as all the other stuff we will use it for/ freezers...Again, power comes back on and they recharge while your refilling you’re backup water system. If you use battery power, take a look at the marine setups for 42 foot plus boats. Some nice desalination and filtration systems that are well built and designed for small four person water production needs. You may not need the desalination but the ability to filter waters is certainly there and there may be some nice options without the desalination angle. Boat systems are usually nice robust and compact units made with top quality stainless steel and quality plastics. In fact, I would highly recommend people look at any boat system component if they want something made well. 12 volt water pumps for flooded basements, inverters, faucets...... the systems are often exposed to continual vibration, heat, humidity, salt air... and need to function when needed.

Sorry I couldn’t provide product names but given the energy options of a person living in the city, I think this may be worth looking into.

Find a good UV and then make sure the bulbs are a good price. The guy that installed the one in my place bought the cheapest system, with the most expensive bulbs and the hardest to find. I use to have to get it special ordered from a water depot guy. I get them about $20 cheaper on amazon now..... but tsc has similar systems with bulbs half the price of mine.

No power..... no problem, break out the drip filter or boil it. (You have a wood stove). We don’t have summer any more do we?

We've got one of these: http://rainfresh.ca/product/undersink-water-filtration-system/

I'm comfortable recommending it.

We have it mainly because we're in an older area where there's some question of lead water feeds (we had to get our feed replaced, but who knows what might have built up or what's on the public portion of the supply). Also, you'll be amazed how dirty the ceramic filter gets. And like the OP writes, if anything were to happen to the water supply -- and it can happen even in Canada -- you'll be OK.