Solar IBoost+ experience

Screwdriva

Bulb Energy, who I am with, will pay 5.38p for export. Since my heating & hot water comes from Natural Gas, I assume iBoost won’t make sense for my household unless I use the Megaflow tank’s immersion heater and bypass the gas boiler.

Hexane

Screwdriva wrote: »

Bulb Energy, who I am with, will pay 5.38p for export. Since my heating & hot water comes from Natural Gas, I assume iBoost won’t make sense for my household unless I use the Megaflow tank’s immersion heater and bypass the gas boiler.

Correct, if you have the ability to heat your hot water with gas, and you are being paid 5.38p per kwh for metered export, then an iBoost for domestic hot water heating cannot make sense unless the device and installation are both free. Bypassing the gas boiler doesn't really make a difference.

Mike564

I have a 3kW Solar PV system with a 4.8kW Social Energy battery. I also have an IBoost. The IBoost seems to divert power to the immersion when the battery is feeding the grid (sells to the grid at peak times). My question is this; would I be better off doing away with the IBoost as it must be detracting from what is actually going back to the grid and therefore costing me money made from the Social Energy system?

thevilla

I remember Alan Sugar was forced to add a fan to the original Amstrad computer by his accountants to make it look 'professional' and always think of that when the iBoost noise issue comes up on these forums.

I have an Apollo Gem https://www.apollosolarelectric.co.uk/ which works fine in the airing cupboard with no fan heating the water and a towel rail.   It will never pay for itself as it replaces gas but it is there so will stay until it breaks.

Sterlingtimes

The economics for the iBoost will vary from household to household and from time to time. Presently, in a gas household with metered export of electricity, economically I should always burn gas provided that the efficiency of producing hot water by gas is greater than 55%. I have mounted a pixie filament bulb connected to the iBoost outside the airing cupboard to tell household members that plenty of free electricity is available for domestic appliances.

pinnks

From my perspective, using gas to heat the hot water when the central heating is off costs about the same as using electricity via the immersion.  This is because I have significant losses on the boiler/gas system as there is a round trip from boiler to tank of about 22m of uninsulated (under the floor) 28 and 22mm pipes.  This is based on actual gas savings over the summer months compared to energy diverted by the immerSUN.  For this reason I use electricity rates to calculate the return on my immerSUN

westfielder

I have an iBoost+ that failed after 18 months. Being an electronics engineer many years ago (and tight) I didn't want to chuck it.
As per others, my unit was diverting power at max current all the time. independent of the time of day etc. 
I found that the IGBT, the component that does the diverting had failed. Also a diode in the driver circuit. So I replaced both and the unit is working again. However the fan wasn't running when the unit was diverting - I was disappointed to see on here that it should have been!
Hmmm back to some more checking

Nick

westfielder

Well it's counting the watts, diverting the power and I can run the fan with the fan test function. I think I may have damaged the circuit that does the fan switching on the smaller control board. Frustrating.

If anyone is chucking theirs out 'cos it's failed, I'd appreciate the smaller control board - please contact me.

Alternatively, I might rig a 5v supply to the fan via an old 5v DC power plug supply for an old CD player and run it off the output to the heating element. I guess that would do the same job. 
Thanks

Nick

JKenH

My Solar IBoost+ died yesterday at the tender age of 2 years and 8 months - completely dead, blank dull screen with no response to any button pressing. 

I spoke to Marlec about a service exchange unit which they supply at a discount if the unit is less than 3 years old but after talking it through it seems my installation may be the problem. They asked me how long my cable run was from the IBoost to the  Immersion heater - it is over 15m and therein lies the problem. Apparently long cable runs act like an aerial and pick up a lot of “noise” which over time damages the electronics. They said ideally cable runs should be less than 3m (or use a screened cable) so in my situation a replacement unit would also be likely to fail over time. (The unit was installed in a bedroom adjacent to an en-suite bathroom but the noise of the IBoost fan was so loud I had it moved to the landing, hence the long cable run). 

I had enjoyed the IBoost which had initially been saving me somewhere in the region of 1000kwh but since installing it my circumstances have changed. I now have 2 ASHPs which I run during the day and I also have a Zappi charger for my Leaf so the amount of spare electricity I have is much reduced particularly in winter. I would still have spare PV for about 8 months of the year but since moving from an E7 tariff to Octopus Go the cost of heating water on a cheap rate overnight has almost halved. The annual saving I could achieve is now a maximum of £50 so, given that the life of my last unit was less than 3 years and the exchange cost is about £150, I am inclined to go back to a basic E7 type timer and try the odd manual boost on very sunny days. (I did consider whether to try an Eddi as I already have a Zappi but am concerned that it might suffer from the same “noise” problem.)

PS I now have an IBoost Buddy for sale. 

Solarchaser

Hmm... I don't see how the length of a supply cable after what is effectively a switch would make any difference to be honest. 

If you had said from the ct clamp to the iboost, then I could see the logic in signal interference causing an issue with the unit causing erratic operation and putting undue stress on the unit, but I struggle to see how length of supply cable would cause it.