Voltis Home -voltage optimiser - Anyone actually got one?

zeupater

Murchison2003 wrote: »

Cardew
The thrusts of my posts are that since i have fitted my Voltis, i have seen a definate reduction in my kwh usage every month since it was fitted. Having the heatpump obviously uses more electric than an ordinary domestic user hence why i am seeing the results. This is my whole electricity use not just my heat pump.
The initial question was does anyone have one and does it work.
My statistics say yes. If people want to bash it fine, i can't find any reason to.

Hi

I think it's clear that no one here disputes the fact that you have seen a reduction .... what everyone else is attempting to convey is that the timescale which your dataset covers is not sufficient to conclude that the saving is entirely, or even partially due to the voltage optimisation device.

Returning to why .... to help illustrate the effect of the abnormally warm winter period included in your energy consumption dataset I've take time to perform the following analysis. Taking the core heat provision period as being the five months November through to March, (according to the CET dataset) in over 350 winters since 1659 there have only been 10 which have been as warm, or warmer than the last one ... these for information were (by Spring Year) 1686, 1734, 1822, 1834, 1989, 1990, 1995, 1998, 2007 & 2012 ... which cannot simply be dismissed as not being relevant.

As can be seen, the only winter which is within your monthly energy usage dataset which would seem to be of any use for comparison would be the one for 2011/12, so here's the CET monthly breakdown ...

Mth - 2012 / 2014 (C)
Nov - 9.6 / 6.2
Dec - 6.0 / 6.3
Jan - 5.4 / 5.7
Feb - 3.8 / 6.2
Mar - 8.3 / 7.6

... with the average daily values for that 5 month period over the last 5 winters being (degreesC) ...

2010 - 4.4
2011 - 4.3
2012 - 6.6
2013 - 4.2
2014 - 6.4

These figures can be used to calculate how the heating energy demand for a constant indoor temperature property would be reasonably expected to vary by year.

HTH
Z

zeupater

Hi All

Okay, I've had my evening meal and a cuppa .... so let's spend a little time running a 'quick & dirty' sanity calculation to establish what the 5 month winter heating load difference would be between last winter (2013/14) and the previous one (2012/13).

I would normally expect the averaged temperature throughout a modern well insulated house to be closer to 20C than the 22.5C mentioned in post #10, however, lets just work on the higher indoor temperature even though it would dilute the effect of this calculation by a substantial factor ....

Whatever energy was actually used, as long as the indoor temperature was substantially the same both years (and it's been stated that this is the case) you would reasonably expect the percentage difference to be related to the relative averaged indoor to ambient differential for the two years, hence 16.1C(22.5-6.4) for 2014 against 18.3C(22.5-4.2) for 2013, a saving of 12% .... as mentioned, this is a pure sanity exercise based on the indoor 22.5C given .... just for fun, a 20C averaged indoor temperature would resolve to 14% saving with 18C resolving to 16% .....

The figures calculated above throw a very strong cautionary question over whether the assertion the coincidence raised in the statement in post#5 .... "Over this past year i have seen an approx 18% reduction in my electricity bill, coincidence? don't think so" as it seem that the vast majority can be attributed purely to ambient temperatures. As previously mentioned, the only coincidence at play here seems to be an exceptionally warm winter happening just after the voltage optimisation equipment was installed.

Of course, arguments can be made that CET doesn't apply because the installation is outside the CET area, however, although our local MetStation shows different monthly and annual figures to the CET dataset, the anomaly is remarkably consistent ... this suggests that the use of the CET dataset & the logic employed above is likely to be pretty sound.

HTH
Z

Murchison2003

Cardew
Do you really think i'm some sort of sales rep plugging these things on a forum?
Are you some sort of comedian?

Dave_Fowler

I use gas to heat the house.

The winter of 2012 - 2013 (1st November to March 31st) gas usage:- 13043 kWh
The winter of 2013 - 2014 (1st November to March 31st) gas usage:- 11143 kWh

That's a drop of 14.56% for last winter.

Perhaps the gas pressure was lower last winter

Dave F

Cardew

Murchison2003 wrote: »

Cardew
Do you really think i'm some sort of sales rep plugging these things on a forum?

Frankly, yes I do.

Murchison2003

Martyn1981
At last, someone who seems to be on the same wavelength as myself, not like some of the ejits that spout off on here.
I'll hopefully answer some of your questions.
My heat pump will not give me full kop value for a few reasons. The underfloor heating system was designed originally for an oil heated system with water temperatures of 55 degrees, hence the spacings in the pipes below the screed are wider. The temp of 22.5 degrees is that of choice as i have a wife and family that likes to bake most of the time. Kop's of systems are usually worked out for room temperatures of 21 deg. My system runs adequately at 32 deg to keep my house at 22.5 deg. The floor area i am heating up is 248 m2 so i think is above average size of house. If this was designed when i built the house the heating pipes would have been fitted closer.
It is well insulated but not super insulated.
The coil collector length in my garden is the minimum that i could achieve, i only had 700 m2 of garden to put it in, a longer coil would have been beneficial however i was assured by the suppliers that it would work sufficiently.
My pump doesn't have a heat meter but does have running hours so consumption can be worked out. At the time it was estimated to run at 8700 kwh for room temp 21 deg. That's 8700 x 10p =£870 compared to 3000(litres) of kerosene x. 65p (price at the time of thought) =£2010, at that time 5 1/2 years payback, which is this year.
Hope this makes things a bit clearer. Thanks for not knocking the voltis, i am not a salesman of any kind, i just like to give credit where credit is due.

albyota

I run an air source heat pump in a well insulated house with UFH, my consumption has reduced by approx 3,200kWh on previous 12 months and I do not have a voltage optimiser, it's purely down to the milder winter.

Good post Z, respect.

Murchison2003

Cardew
Well i'm afraid your wrong.
This is getting a bit boring now let's change the subject.
What's your opinion on the independence vote.
Would it be good for Scottish independence or worse for England to loose Scotland?
Why do you think Westminster wants 'better together?'

Murchison2003

http://www.savepowerathome.co.uk/howitworks

Murchison2003

Albyota
If your consumption is down by 3200 kwh on previous 12 months, do you mind me asking your Ashp consumption for previous years.