Voltage optimisers Are they worth the outlay ?

[Evans Electric]

Looking at literature for a Voltage Optimiser.

It appears to be a variable transformer fitted between the mains and the consumer unit.

When it senses a load it will reduce the voltage to, eg; 218V . A quick calc and I got a 3KW Imm. Htr. saving 1.15A .

But what about the losses in the Optimiser's transformer ?

I always thought you can't something for nothing in physics .

So your electric meter reads the current drawn by the heater @ 218V plus the losses in the transformer , equalling the same as without the Optimiser? Or is their transformer 100% efficient I ask myself?

I offer this for discussion .

 

[Andy™]

the immersion may be using less current, but it will take the same amount of power to heat the tank, so it will just take longer to heat up.

so overall, including the losses of the 'optimiser', it will use more electricity to heat a tank of water than it will without it

 

[Evans Electric]

Thats what I thought , as you say , longer to heat the tank .

The advertising for the device is quoting the fact that appliances are manufactured to 230V now, not 240V but Britain is still higher than other countries so the Optimiser balances that out and produces a saving.

 

[Sidewinder]

No they are not worth while except under a few very limited situations

 

[Evans Electric]

I was just re-posting and again it has been swallowed up and spat out while I was halfway through .

---------- Post Auto-Merged at 21:56 ---------- Previous post was made at 21:53 ----------

If I tupe roo quackly I mick lost ov mestikes butt terz a tyme limet now bin interduced .

 

[SPARKY51974]

There are s few different types some suggest you cut tails and place full db on optimiser but you cannot put solar pv on it. There are others that you supply with a 50 amp mcb then feed one of your RCD protected circuits but does advise you can't have immersion heaters or electric showers or oven etc ie anything with elements. I have only fitted one customer had it fitted to lighting circuits socket circuits etc and they are really happy saying it has saved them money already. they have a very large fish tank home cinema ect so it must work to some degree

 

[professional]

No they are not worth while except under a few very limited situations

I agree entirely.

They appear to be a vehicle for the unscrupulous to fleece the vulnerable in the name of "progress" ....

 

[kerching]

I went into this a while back, customer wanted it. New build 1 db at one side of house 1 db at other [F big house]

Client talked to manufacturer and I put 2 boards at each location. 1 for the 'Optimiser supplied circuits' and 1 for the 'thermostatically controlled stuff', cookers, water heater etc.

Client dug a bit deeper, did a few sums and got me to connect up without the optimiser, he never even got around to buying them [would have needed 2]. He said that 'when the laws of physics change and the earth shifts on its axis he will reconsider, until then he is still happy with the "energy cannot be created or destroyed, merely converted" and Splnchniks second Law which, to paraphrase the great man, states ..."....if it smells like bulls4it, tastes like bulls4it, looks like bulls4it, feels like bulls4it then it is almost certainly NOT a large crock of gold..."..........I stand to be corrected {obvious choices, Vorderman, Willoughby, Minogues, Huq, Griffin, etc]................ :Y

 

[ParkySparky]

Edf energy are fitting these to all morrisons stores, reducing voltage to around 223v single phase and it reads on average 386 phase to phase.

Morrisons say it reduced there bill alot!!!

They install them between the lv switch on the transformer and the main air circuit breaker. So there rated at 1600A per phase!

Never understood it really, if you took it right back to basics then surly if you reduce voltage then current goes up?

Obviously more to it than that but edf are pushing them big time!!!!

 

[Andy™]

Never understood it really, if you took it right back to basics then surly if you reduce voltage then current goes up?

depends. anything with a switch mode PSU (most electronics) will use more current at lower voltage to keep the same output

everything else will use slightly less current, but you wont get as much use out of them, i.e filiment lamps will be dimmer, heaters will take longer to heat something etc. as above, energy cannot be created or destroyed

and if morrisions had their own transformer, i doubt they would bother with one of them - just change the transformer tapping to a lower votlage...

 

[ParkySparky]

All the tappings on the transformers are at there lowest already and there still fitting them! They got the voltages down to mid 230's on most stores with tappings! Although I work at the freezer distribution warehouse in Corby and the voltage is nearly 250v! Ballasts and lamps don't last very long there!!!

Edf offer 'free' installation, as they basically split the reduction in bill untill the kit is paid for, so say for example if it saves them

 

[Sidewinder]

So, are these voltages presented within those prescribed by ESQCR?...

 

[ParkySparky]

216.2v to 253v so I would say yes.

 

[unphased]

The VPhase will adjust itself to current demand and switch out of optimisation mode. The demo I attended used a tungsten filament lamp. At 220V there was no discernable difference in the brightness of the lamp but reducing voltage further made the lamp appreciably dim. Tungsten filament lamps are being phased out and the replacements are intinsically energy efficient anyway, LEDs and CFLs.

in the case of heating elements the physics is as described. Boiling a kettle will just take longer. However, is the heat gradient directly proportional to the time taken to heat the water to the same temperature? I don't know. There must be an optimum amount of water to be heated in a kettle over a certain time period. A kettle is not insulated either. There must also be an optimum power requirement aginst time to heat cylinders filled with water. There must be some truth in the claims made by voltage optimisers else Morrisons et al would not be investing in them.

ut the kettle on

 

[Andy™]

7671 Amendment 2 coming out next year

Max volt drop with v-phase installed - 0.05%

 

[sprocketflup]

a solution to a problem that doesnt exist then?

Deke, I have some snake oil you maybe interested in....

 

[user 15807]

Thats what I thought , as you say , longer to heat the tank . The advertising for the device is quoting the fact that appliances are manufactured to 230V now, not 240V but Britain is still higher than other countries so the Optimiser balances that out and produces a saving.

I attended the V-Phase training day at my local wholesalers. They clearly stated that the V-Phase only produces a saving on lighting as it reduces the voltage which inturn provides the same amount of light but reduces losses as heat and may increase lamp life. The V-Phase does NOT save anything on Heating loads, Showers, Cookers and Immersion Heaters, if you lower the voltage the current increases therefore the heater is still using the same amount of power.

The idea behind it is that lamps are designed for the european market which is 220-230v they will run better (according to V-Phase) on the correct voltage. If you read the spec for V-Phase it shows a graph with a curve for how long the v-Phase will work on a given load before overheating and automatically bypassing, it literally closes a contactor which shorts out, the in and out terminals rendering the unit useless until it cools down.

I decided after doing the course it is 400-500 quid to supply and fit, it may save you some money but if you load it heavily (even a large domestic installation) it will not be in circuit that much thus not saving much. I really liked the idea but came away thinking I can save 400-500 quid by doing nothing!

Still, if you would like one, I will pop round and take your money (Sorry V-Phase). Maybe in a few years with some further development it will be a better proposition.

I have been contacted by a contractor for some social housing which were proposing to fit the V-Phase and another make which I forget but the other unit was designed to fit into the incoming tails making installation Much cheaper and I guess a larger capacity if able to handle the whole installation.

 

[Andy™]

They clearly stated that the V-Phase only produces a saving on lighting as it reduces the voltage which inturn provides the same amount of light but reduces losses as heat and may increase lamp life.

if you lower the voltage, then lamps will dim. you cannot get the same light output if you put less in

 

[unphased]

[quote name='Andy

 

[Sidewinder]

Yes they will dim, but as I said in my earlier post, there is no discernable loss in light output at 220V, which is what the VPhase optimises at. If you take voltage reduction lower than 220V you can tell the difference in light output. I would have thought that companies like Morrisons would be investing in commercial power factor correction systems.

They almost certainly have PFC equipment, else they will be penalised by the DNO if their PF strays too far from unity.

However PF & voltage "optimisation" as in the VPhase, are 2 different issues.