Well I'm sitting here once again furious that we are beholden to the blinkin' electricity companies. The story goes like this...
We moved from Scotland to France with the idea of making all our heating and hot water requirements as sustainable as possible. To this end we ordered an Esse woodburning cooking range with a large back boiler (we call her Jesse the Esse) and a Canadian water/air heat exchanger unit to blow warm air into areas of the house that didn't quite get the warmth from the cooking range. All was installed at great expense and with a large hot water tank (1000 litres) that has so many dials and controls on it that it looks like a rocket - hence the pet name Roger (Rocket).
The water/air exchange unit has never been a great success - it's noisy, blows cold air for the first 5 mins and drains Roger of heat faster than pulling the plug on it. If it's REALLY cold we sometimes use it for 20 mins.
Jesse works wonderfully, providing great ever-ready cooking facilities, nice warmth and hot water.
But the most annoying bit is that Roger is 6m (18ft) away from Jesse and needs a little 150W Laddomat pump to keep the hot water moving up to the tank. If there's a power cut (which is what there was again yesterday for the 6th time in 12 weeks, and focused my mind) we have no pump and so all the hot water from Jesse pours out of the overflow pipe at the back of the house. That leaves her boiler empty and so we have to throw sand on the fire immediately so that we don't wreck Jesse. As we had to do yesterday just as I was about to start cooking pizzas. Grrrr. It's galling because we knew that there were many power cuts so we thought we had a system that, being wood-fired, we could still cook on, have heat from, and hot water even if there was a power outage. But we don't - we're just as dependant on the Big Boys as everyone else
Ok, so now we need solutions.
We have had some French companies come in to speak to us about installing PV but they're only interested if you're going to ship the power out to EDF, France's main electricity supplier. Two said that they'd size up a quote for being autonomous but despite being chased, have never sent the quote.
First thing that comes to mind is battery backup, or maybe a biofuel electric generator. In an outage, day or night, you might be able to run the pump long enough to finish the pizza.
Solar sounds like a good idea, and if the grid goes down who's to notice you stealing your own power back? If the grid is wobbly I can understand them wanting to bring more solar online. See if there's an option to produce grid power for now, and convert to autonomous after their lease runs out, or when the grid's down.
Generally my husband and I are moving away from forced-air heat, even a hot water bottle is more effective.
He's done a lot of DIY plumbing, electrical, and even superheated steam (he was a boatswain for a while, and I gather they can do anything it takes to get the hull home, including machining spare parts out of soup cans and epoxy at sea).
If you have someone like that around, maybe they could give you an option on a secondary, non-electric pump. You want to be very careful, there's good reasons for the overflow provisions, but if you can safely re-capture that overflow and get it where you need it, would that solve the problem?
Sounds like Jesse needs Roger on line to cool her down. Are these Esse ranges always codependent like that, or would she normally be refilled manually? Can you just refill Jesse from the tap and keep on cooking? Maybe not with cold water right into a boiled-dry tank, but if you can anticipate it early enough to top off while the tank's just warm... although I bet Roger's dials are supposed to monitor that, and if they're electric, he's asleep at the wheel just when you need him.
I'd ask the nice folks whose equipment you actually like (Esse) to take a look with you, and give some options for keeping yourselves in bread and water when the fancy boyfriend lets her down. Or maybe consider whether it's time for her to end the relationship.
Make sure you got a good hydro- or boiler- helper if you go re-routing the pipes, though. Thermosiphon plumbing and boilers make alarmingly good pipe bombs if you get a valve or bubble in the wrong place.
Sadly we can't 'nick it' from the grid when the power's out as it's all locked up and cabled separately. Plus the 'lease' is for 25 years and I reckon the panels might be a bit done by then.
Yes Jesse does need Roger. In back-boiler mode they are co-dependant and it makes me wish that we'd gone for the cooking only model. Can't refill manually. We did whip off round to the back of the house to collect some of the hot water coming out of the overflow in a bowl so we could have a cup of tea The whole system was only installed a year ago so sadly we can't end the relationship - sigh.
I guess I need to ask some questions around how to link up a generator or battery. How do we feed the alternative source into our system? I bought a DIY 12V book but then realised that most of our appliances (including the Laddomat) say on their plate that they need 230V so I felt disheartened again. Can anyone explain in dummy terms what needs to happen?
I would look at motor home appliances DC is the better way to go for lowering costs in many cases. boats and motor homes are often all 12V or 24V DC. they run out of battery banks and some sailors i know have figured out how to run things raw from the solar panels or wind generators. its funny these days to think that sailors are on the cutting edge of efficiencies.
Need more info?
Ernie and Erica
Wood burning stoves, Rocket Mass Heaters, DIY,
Stove plans, Boat plans, General permiculture information, Arts and crafts, Fire science, Find it at www.ernieanderica.info
How long are your outages? If they are short perhaps an uninterruptable power supply (UPS). You would need to put in some manual override valving but the UPS would give you time. A diversion/emptying of a small part of your system, ie in direct fire contact, may be required but you would retain most of your cubic metre of heated water. A small one plus a small auto start generator would fix most of your woes. You're in the same trap as many friends who went with pellet stoves for heat, no power = no heat.
It has the battery built in, you plug it into the main and your system into it and it does the switching for you. Unless you go to quite a lot of expense you won't have a system that will get you through a 48 hr blackout on batteries alone. This gives you time to manually shut things down so you don't loose your hot water or time to get a generator going. Add a mains cutoff switch, you don't want to fry any linemen working on restoring power, plus a small generator, ~1000W will do everything you need for the smallest price, both these can be manual or automatic with the latter more expensive but it does everything for you, unless you can hack a system together yourself or have a friend that can. From what you said earlier there's a valve that opens automatically if the power goes out so being able to manually move the power cord will mean losses. If you want to do a DIY hack I'd suggest going to
Hen, who set up your hot water heating system with the Esse? We just bought the exact same stove (being shipped sometime this month!!!) and we're puzzling over the installation diagram.....it's a fairly complex set up. It looks like such an amazing stove......I can't wait.....but I'll have to for awhile as it sounds like the water system needs to be set up before you can use it at all (which is what we figured, I'm not excited about waiting til our "real house" is done to use it but I guess I might not have a choice).
Ok, I'm not an electrical genius but here's my idea from what I do know: 150 watts isn't a huge draw on a good sized battery, but like mekennedy said if you manually have to switch the plug you're still going to lose hot water out the back of the house. I'd suggest having the pump permanently connected to and powered by the battery, which can be set up to be charged by the grid, and when the grid goes down your pump would just draw off the battery's stored energy. Depending on your battery, you could run only the pump off the battery for a few days. This is the simplest way I see to deal with the pump situation, as it sounds like that the biggest challenge of the electricity going out. If you want a more elaborate PV system to power other things you'd have to invest in more panels, etc.
Weird the professional guys aren't calling you back....I'm assuming it's a cheaper set up to opt out of feeding back to the grid? Is it legal to have an autonomous system? Do you care?
As MeKennedy already pointed out, one very easy option might be to simply purchase a fairly high wattage rated UPS unit intended for 230vac european home computers. If the UPS unit is rated much higher than the 150 watt pump motor, it should work out fine to simply run the pump motor plugged into the UPS unit all the time.
I do exactly the same thing to keep the air circulation fan running on my wood stove when the power fails. I have a 100w 120vac fan motor running on a 400w rated UPS unit ... which coincidentally runs about 4 hours on the unit's 'internal battery' power when utility power fails ! I think the complete UPS unit cost me like US $40 at Staples.
I do not know what the rules or codes are in Europe,
but for generators or other type of systems that would take over from the power company, a double throw transfer switch is required in the US, (there are some other types as well, but the system is set up that only one can be connected at one time, so the grid can not feed into the generator or inverter or vise versa. on some units they have what is called an automatic transfer switch, which will switch on the lose of power and start the generator or link on to the inverter if that is the back up system, so it works like more like a computers UPS, (but there would be a blink in the power as the switch occurs depending on the type of system it could be up to 30 seconds (until the generator get started and self checks out). (of course the more automatic the system is the more expensive it becomes).
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