Monthly Archives: October 2018

Smart meter and tariffs

Earlier in the week I received notification from my electricity and gas supplier that my 12 month contract was coming to an end.  I did my usual search for the best value Economy 7 tariff but drew a blank – everything including renewal with my existing supplier was rather more expensive than I’m paying now – so I decided to be rather more adventurous.

My decision was a significant change – not just a move from Economy 7 to a smart meter, but also the addition of a smart tariff (one that changes rate multiple times per day), and indeed my chosen tariff is dynamic so it potentially changes every half hour and day-to-day.  As I don’t yet have a smart meter then I’ll continue on Economy 7 until the meter is replaced, but then adopt the dynamic tariff.  With flexible loads like electric car charging and my storage battery then I should be well equipped to make the most of such a tariff.

On the dynamic tariff rates are published each day at 4:00 PM for the next day.  Some times (not very often!) prices even go negative so one is being paid to consume.  At other times electricity is relatively expensive (early evening’s principally) but the battery should help me minimise purchases during such times.

I’ve already checked the battery storage and it has the ability to be programmed very flexibly around different electricity prices at different times of day so that it doesn’t just absorb surplus solar but charges at lower cost times to discharge at higher cost times.

I also want to explore opportunities to automate the response to tariff changes – potentially linking storage battery, car charging, and water heating to tariff as well as self-consumption.

Smartie pants

Of the course of the last year or so I’ve gradually created a smart home system with in the teens of components as follows:

    • 8 Eve Thermos (eTRVs) which replace the standard TRVs on the radiators.  These eTRVs are programmable for both temperature and schedule, replacing the previous central heating timer at home level with multiple timers at room level effectively creating a multi zone system.
    • 3 Eve Window switches which detect open windows.  These illuminate a warning lamp and/or disable heating of that room while the window is open.
    • 2 non-Eve smart bulbs. Both of these operate on a dusk-to-dawn schedule while one also illuminates in a colour when any of the 3 monitored windows is open.
    • 2 Eve Motions.  One of these adjusts the lounge heating in the evening based on room occupancy so that the heating is disabled earlier in the evening if the room is not occupied.  The other is as yet uninstalled.
    • 1 Eve Energy which is a remote-controlled outlet that turns the gas boiler on or off based on heating demand from the eTRVs and a couple of rules.
    • 1 Apple TV box which acts as a home hub for monitoring the devices and running multiple rules which operate lamps and outlets based on input status.  Currently input is taken from valves, windows, motion, and external dusk/dawn signals and outputs sent to other valves, lamps, and socket outlet.

At the moment I tend to add a new device each month – if I can think of a useful function that it can perform.