navitron
 
Renewable Energy and Sustainability Forum
Welcome, Guest. Please login or register.

Login with username, password and session length
News: Anyone wishing to register as a new member on the forum is strongly recommended to use a "proper" email address. Following continuous spam/hack attempts on the forum, "disposable" email addresses like Gmail, Yahoo and Hotmail tend to be viewed with suspicion, and the application rejected if there is any doubt whatsoever
 
Recent Articles: Navitron Partners With Solax to Help Create A More Sustainable Future | Navitron Calls for Increased Carbon Footprint Reduction In Light of Earth Overshoot Day | A plea from The David School - Issue 18
   Home   Help Search Login Register  
Pages: 1 2 3 [4]   Go Down
  Print  
Author Topic: Introduction and off-grid living questions  (Read 10829 times)
biff
Global Moderator
Hero Member
*****
Offline Offline

Posts: 12305


An unpaid Navitron volunteer who lives off-grid.


« Reply #45 on: November 12, 2015, 10:44:30 AM »

      " Although some people do seem to enjoy an never-ending challenge"
                   freeze freeze
                                        Biff
Logged

An unpaid Navitron volunteer,who has been living off-grid,powered by wind and solar,each year better than the last one.
V
Full Member
***
Offline Offline

Posts: 157



WWW
« Reply #46 on: November 12, 2015, 12:44:00 PM »

I'm with Heatherhopper here. The electricity infrastructure is creaking - here in the southwest they can't export any more renewable energy to the rest of the country until they upgrade their cable, which isn't happening until after Hinkley Point is finished. I go to friends and find out they've had power cuts and we haven't noticed.   

Yes it is testing and scary sometimes, but it does work, extremely well. We're trying to help our neighbours to do the same as us when they convert a remote barn for a holiday let. And everyone here on the Navitron list has helped us get to this point. The point where we hardly even think about where the electricity comes from anymore.
Logged

9.7 kW of Solar PV, 3x 3000 SMA Sunny Boys, 1x SMA Sunny Island  8.0 and 1848 aH (C10) of FLA - 3.3kVA Honda generator converted to LPG
readiescards
Newbie
*
Offline Offline

Posts: 14



WWW
« Reply #47 on: November 21, 2015, 07:53:47 PM »

Great thread - as this is very much me!

Quote
At the moment I am flip flopping back and forward between the two options of A) play it safe, pay for the electricity utility to be brought on site, design and build a good PV, medium battery, grid and generator system but not feed in while we learn our new energy usage and B) jump in the deep end, not spend any money bringing 'leccy in and use that to finance our first battery bank and be fully off grid. It would be 8kWh+ of Solar PV only at first but we would have to ensure our usage was covered in the worst month with generator cover while we investigated locally available wind.

And biff's comment:
Quote
I took this into the bedroom and read it out to Mrs Biff. She laughed and said that you will be lucky if you are not divorced by the time you get it right,

Hits the nail on the head too!
« Last Edit: November 21, 2015, 07:55:31 PM by readiescards » Logged
DanielCoffey
Jr. Member
**
Offline Offline

Posts: 87



« Reply #48 on: December 06, 2015, 11:23:59 AM »

OK, we're back. The inherited house sold successfully and we have what was left of the post-solicitor sale proceeds.

We have an appointment scheduled with an Architect to conduct the first sanity check of our requirements for our future bungalow and I would like to make sure I am asking him the correct questions about the PV, inverters, batteries and so on. I would also like to make sure that I know how to explain myself correctly when I ask about gaps in my knowledge.

Given a grid-tied but non-FiT property (as it will be late in 2016 before it is complete) with, say, 6kWp to begin with and a 48V FLA battery bank in an external but insulated store...

1. What *type* of Inverter and battery management system would we be looking at? I don't mean brands but rather the names of the components.

2. I would assume that by not feeding in, it releases us from the need to pay extra for MCS Certified installers and kit. Is that assumption correct?

3. In the event of a mains power cut, will the Inverter automatically switch the property to the battery or will it drop off because it requires mains to keep going? If it drops off, what do you need to have fitted (such as UPS) to keep it going or do you have to switch over manually?

4. Are there any critical single points of failure in such a system that would cause the entire system to be down if something failed? I mean some component that if it broke, would leave the entire household without power until it was serviced or replaced. Would it be advisable to have a "cold spare" of this component either in a box or actually wired in but isolated?

Since the Architect is going to be making a specific visit to us, I wanted to ensure I was asking all the correct questions at this meeting in the correct way. I don't want to have him go home thinking I am a blithering idiot.
Logged
billi
Global Moderator
Hero Member
*****
Offline Offline

Posts: 9073



WWW
« Reply #49 on: December 06, 2015, 02:10:08 PM »

....  will the architect   design  a complete new house ?

If so , i would ask him , if there are   cost efficient options  for  roof and facade  designs  to save some   , cause they are hidden anyway by PV  solarwatt  for example  http://www.solarwattuk.com/architectural-construction/     and talk about roof Slope (winter)  and orientation 

On the otherhand i read that  Solar PV hybrid panels   are getting  Renewable Heat Incentive payements , but do not know the  costs of those  ....

To your Questions


Quote
. What *type* of Inverter and battery management system would we be looking at? I don't mean brands but rather the names of the components.

Off-grid/hybrid inverter  3-5 kw power , depending on your  electric use,  one 80 Amp  Mppt chargecontroller  (if   6 kw PV is max  )  and a battery   and a battery monitor   (this is the basic setup )

Quote
2. I would assume that by not feeding in, it releases us from the need to pay extra for MCS Certified installers and kit. Is that assumption correct?

I assume so as well  , but i assume  that you have to , if you use an Grid tie inverter  coupled to the offgrid inverter , instead of my suggested chargecontroller

Quote
3. In the event of a mains power cut, will the Inverter automatically switch the property to the battery or will it drop off because it requires mains to keep going? If it drops off, what do you need to have fitted (such as UPS) to keep it going or do you have to switch over manually?
The Off-grid/hybrid inverter   , will do that automatically for you ,  switch to 100 % off grid in case off a powercut ,   or /and as well supply  needed surplus watts from the grid (if available) and ad those missing watts  from the grid , incase the the demand is bigger than the Off-grid/hybrid inverter  can deliver

Quote
4. Are there any critical single points of failure in such a system that would cause the entire system to be down if something failed? I mean some component that if it broke, would leave the entire household without power until it was serviced or replaced. Would it be advisable to have a "cold spare" of this component either in a box or actually wired in but isolated?

I thought you have the Grid ?  It sounds highly unlikely that  the grid is down and your system broken at the same time   whistlie  , but anyway   it can be handy to have a  low cost  alternative Off-grid/hybrid inverter in the shed 4 kw  including chargecontroller  ..... (they start from 500 )


I have not enough time to read the thread again , but  not too sure  again ,  if 6 kw  is  the right  size   (but that depends as well on your heating/system  and hot water needs )

Billi




Logged

1.6 kw and 2.4 kw   PV array  , Outback MX 60 and FM80 charge controller  ,24 volt 1600 AH Battery ,6 Kw Victron inverter charger, 1.1 kw high head hydro turbine as a back up generator , 5 kw woodburner, 36 solar tubes with 360 l water tank, 1.6 kw  windturbine
DanielCoffey
Jr. Member
**
Offline Offline

Posts: 87



« Reply #50 on: December 06, 2015, 05:49:55 PM »

Thanks for the suggestions and info.

Yes the Architect will be designing the property from scratch so we can ask about in-roof panels since they will save us from having to buy (and maintain) tiles. The Architect is based in Ayrshire so is well used to the typical roof pitch in Scotland.

It is nice to know that we have to ask for an Off Grid/Hybrid inverter and that it will easily handle a mains outage automatically. The last thing we would want would be for my wife's pressure-relieving mattress to be flat in the morning if the power went out.

I suspected the Inverter would be the critical component in the system. Now I understand that if any other part fails, all we would lose would be the juice from the panels or the battery but it is the Inverter that ties it all together. I am inclined to have a cold spare actually wired in or at least adjacent so that we can switch over easily but I will talk to the Architect about that at the time.
Logged
skyewright
Hero Member
*****
Offline Offline

Posts: 1769


« Reply #51 on: December 06, 2015, 10:12:21 PM »

It is nice to know that we have to ask for an Off Grid/Hybrid inverter and that it will easily handle a mains outage automatically.
I know you didn't want to get into brands at this stage, but if you haven't already read it I think you'll find this Victron "Whitepaper" intersting. Obviously all the kit mentoned is Victron, but the same things could be done with other manufacturers kit, so just read it as an indication of some of the various ways that things can be wired up if you have both mains & batteries...

http://www.victronenergy.com/upload/documents/Whitepaper-Self-Consumption-and-Grid-independence-with-the-Victron-Energy-Storage-Hub-EN.pdf
Logged

Regards
David
3.91kWp PV  (17 x Moser Baer 230 and Aurora PVI-3.6-OUTD-S-UK), slope 40, WSW, Lat 57 9' (Isle of Skye)
billi
Global Moderator
Hero Member
*****
Offline Offline

Posts: 9073



WWW
« Reply #52 on: December 06, 2015, 10:56:49 PM »

Quote
I suspected the Inverter would be the critical component in the system. Now I understand that if any other part fails, all we would lose would be the juice from the panels or the battery but it is the Inverter that ties it all together. I am inclined to have a cold spare actually wired in or at least adjacent so that we can switch over easily but I will talk to the Architect about that at the time.

to be honest , i would be very surprised , that the architect  knows a lot details  about off grid inverters and chargcontrollers  , ( i do not mean that disrespectful )

My Victron off grid inverter ( i have to 3000w in parallel ) are 9 years old now and no  power failure  since ... touch wood
If you consider a charge-controller ,....  they can break ( i  know )    in a 48 volt setup  you can wire 3 panels in series  to get around 66 volt  , they would then be able to work directly connected  to the battery without a charge controller for a while ( if you grant that the battery is not getting overcharged , and that can be achieved with a programmable  relay , that usually is inbuilt in good  off grid inverter   , also handy to  controll an AC Dump to heat  for hot water or a small heatpump )

Usually replacement of broken  gear is a no brainer with  established brands 

Billi
Logged

1.6 kw and 2.4 kw   PV array  , Outback MX 60 and FM80 charge controller  ,24 volt 1600 AH Battery ,6 Kw Victron inverter charger, 1.1 kw high head hydro turbine as a back up generator , 5 kw woodburner, 36 solar tubes with 360 l water tank, 1.6 kw  windturbine
heatherhopper
Sr. Member
****
Offline Offline

Posts: 376


« Reply #53 on: December 06, 2015, 11:57:11 PM »

Wouldn't disagree with the above advice but still can't see exactly where you are wanting to be long term. You appear to want to invest quite a lot of money in seldom used back-up for grid failure, will a small generator not suffice?
If you are going to want to have stand alone systems you really need to get someone in who understands this kind of thing, and this will certainly not be your architect, specifically someone who has lots of proven experience with off-grid. If not you may end up with a lot of expensive, inappropriate gear or something that falls well short of your expectations or, at worst, a bit of both.
Logged

Off grid AC coupled, 6kW Proven, 2.8kW PV, SMA SI/SB/WB Inverters, 4x576ah Rolls batteries @ 24v, 25kW Biomass Boiler, Wood Stoves, Spring/Well water. Sorry planet - I did try.
billi
Global Moderator
Hero Member
*****
Offline Offline

Posts: 9073



WWW
« Reply #54 on: December 07, 2015, 01:47:05 AM »

Sure HH  ,  it can be a nightmare to get a salesperson to sell a very complicated  set-up
A battery based system (even with grid connection )  needs some attention .... , 

 but a grid tied  battery less  PV  nowadays as well , cause  it seems to make only sense if  the self-consumption is adjusted to the sun*s behavior ....  , or   one just exports most of the PV power without a fair  FiT return ....

...a battery , can be a nice  relaxing  balance as well

My Maintenance is basically   , refill  water  into the batteries  3 times a year (for the PV part )  ,  but surely   watch the production and the voltage   on my battery monitor is  something i have to do , but thats an enjoyment  Grin 

Sure  , it depends on  the homeowner ..., would not make sense to convince someone without any interest   in that theme , but seams  not the case here ...

Daniel  , i read your entry post again 

Quote
My wife (who is disabled - yes this is relevant to subsequent questions) and I are about 50 and currently living in a mid-1930s first-floor flat that is on-grid with Scottish Power in Edinburgh. We have no renewables as the roof is shared with 6 owners. Our current utility usage is 6500kWh for gas (heating and domestic hot water but no bath or shower) and 3750kWh for electric (including a power shower). My wife has two pieces of healthcare-related equipment which are on 24/7 and consume about 50W between them (air pump pressure-relieving mattress and a CAS Alarm with a toasty hot wall wart). We have no income other than benefit as she is severely disabled and I am her fulltime carer.

Now here it gets interesting...

We are about to receive a large lump sum which we intend to put into a new build PassivHaus bungalow of around 120m2 in the Scottish Borders (mid- or eastern Borders rather than the windier/wetter west coast). We are leaning towards the smaller Borders villages (like Clovenfords/Walkerburn and similar) rather than the towns because you get a lot more plot for your cash down there. A finger in the air division of the lump sum would put us in the ballpark of 125k for a plot of around half an acre, 275k for the design and build of the PassiveHaus bungalow and a fairly large contingency to live off for a year while the build was happening and our income-related benefits were stopped.


...When your architect comes  ,... " 275k for the design and build of the PassiveHaus bungalow"  with 120m2 ..... sounds  quite generous    (i guess its single floor  as well)
and  recalculate /estimate your expected consumption figures   for  that new home  , for a passive house it should be under  2000  kwh for heating and hot water , if combined with a heatpump , and your electricity consumption than declines as well ( hot water trough heatpump , more efficient lighting and  other AA+ appliances ?? perhaps )

Again ," an Off-grid/hybrid inverter  3-5 kw power , depending on your  electric use,  one 80 Amp  Mppt chargecontroller  (if   6 kw PV is max  )  and a battery   and a battery monitor "   , i can recommend as a reliable idea

Billi
Logged

1.6 kw and 2.4 kw   PV array  , Outback MX 60 and FM80 charge controller  ,24 volt 1600 AH Battery ,6 Kw Victron inverter charger, 1.1 kw high head hydro turbine as a back up generator , 5 kw woodburner, 36 solar tubes with 360 l water tank, 1.6 kw  windturbine
Pages: 1 2 3 [4]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.20 | SMF © 2013, Simple Machines
SMFAds for Free Forums
Simple Audio Video Embedder
Valid XHTML 1.0! Valid CSS!