On Fri, 08 May 2015 16:38:18 +0100, Martin Brown wrote:

The amount of power required for a tiny burst of data every ten seconds
or so is miniscule. An oil Watchman which sends data much less
frequently lasts many years for example on some very expensive to buy
spares deviously repackaged in copper tube AA Duracell batteries.

Ours a Watchman Alarm, uses a single CR2430 lithium battery, it's
recently complained of being flat. Several years life...

--
Cheers
Dave.