Well said Henno, & especially about annually discussing options with you energy provider.
I actually have a major gripe about off-peak tariff rates.
Some history:
Consumers who had electrically supplied storage water heaters, were given a "J Tarriff" (possibly called a different name in other states) meter, to record the consumption, & that consumption was charged at an "Off Peak" (discount) rate. The reason was, that if the load dropped under the stable load output of the on line generators, they had to shut down a generator & it's super-heated steam boiler. Though a reasonably lengthy process, it's a far longer, more complicated (delicate), & far more expensive process again, to bring back the boiler & generator back to service.
Bringing the huge mass of the steam turbine with it's extremely close tolerances, is a nightmare. The stator is very solid/thick (high mass), so that it will withstand the extraordinary high pressure of the steam being sent to it, while the rotor (the moving turbine blades) are far lighter, so expand quicker. Expansion rates have to equalised, so that the turbine blades don't collide with the stator. The lighter rotors still weight tonnes & spin at 3000RPM. As I hope you can now imagine, it's a very dangerous, expensive process, & it takes a toll on the machine's lifespan due to metal fatigue.
Thing is, the cheaper tariffs were introduced to guarantee a steady load overnight, & it was a great initiative.
I congratulate other states (I'm based in South Australia) that recognise that other equipment be hooked up to the cheaper supply meter, because now the steam turbine generators are way bigger than in the early days, & are even more difficult/expensive to double shift (shutdown & restore later).
Case in point, EVERYONE, should get discounted tariff rates overnight.
Things have change now, in that gas turbine generators (virtually jet engines with a generator tacked on), are all that are being installed now. They're cheap to install, & can be shutdown & restored at whim, which makes life easy for energy suppliers.
Gas turbine generation has been used, though sparingly for decades, to quickly cover extreme peak load conditions, once all of the cheaper to run steam generators were at capacity & unable to cope unassisted. They were used as a last resort, because they consumed extraordinary amounts of natural gas, which was very expensive compared to coal fired power stations. It was a financially driven decision, & at the time, with no thought of conserving natural resources.
So why, oh why, are we all accepting/financing such irresponsible exploitation/corruption by private companies & their investors, who more than likely aren't based in Australia, or give a damn about you & me.
Sorry for the rant, but it's something that dramatically affected my health close to 20 years ago, because it's been lie, after lie, after lie.
