LVP Thermodynamic solar Panels

shane0007

If you are on oil yourself, have your cylinder cold & turn on the boiler to heat it. Time the boiler before it cycles off. Then time the cycles until the cylinder is at 55C.
Then you can calculate the oil usage from the nozzle size to the pump pressure.
I think you will find it uses a lot more oil than you think it does.
Alternatively stick a flow meter on the oil line.

MOTM

shane0007 wrote: »

If you are on oil yourself, have your cylinder cold & turn on the boiler to heat it. Time the boiler before it cycles off. Then time the cycles until the cylinder is at 55C.
Then you can calculate the oil usage from the nozzle size to the pump pressure.
I think you will find it uses a lot more oil than you think it does.
Alternatively stick a flow meter on the oil line.

That could be difficult at the moment - the solar collectors have the cylinder piping - last time I'd to use the boiler was a few weeks ago with 15 people staying in the house. Was like a youth hostel. I'll probably look closer at this in X years if I can ever afford to revisit the heating system. :eek:

shane0007

The reason I calculated oil consumption from nozzle size & pump pressure is because of the huge amount of variants from the nozzle to the cylinder as every boiler differs, pump head, distance, heat loss, cylinder coil, etc.
The only definite I can calculate on is the oil in & the defined kw required to heat a given volume of water in relation to time taken.
You will find my calculations are not off the mark & for people with completely zoned systems will find the levels of oil used outside space heating times of year is significant.
The other benefit not always given serious consideration is the fact that the cylinder coil is completely eliminated during winter months from the oil also. Therefore rads will heat up much quicker, as the coil is not creating a nice open route for it, the house will heat quicker so the room stat should turn off the boiler quicker.

MOTM

...and on the LVP system running costs, if the assumption is 250L at 55 degrees:

250L/d at dT=45 degrees.
[250*4.186*45*365/3600] = 4774kWh with 1162.3kWh electrical input from Braka's system.

Either the 250L/d is wrong or his system has a COP of 4.1.

Given the lack of independent accredited data for this system (as far as I can tell) and the accredited COP to EN16147 for other systems here: http://institute.ntb.ch/fileadmin/Institute/IES/pdf/PruefResWEW130410.pdf

...I'll wait until I see independent results for LVP first. Meanwhile, its too hot outside to be thinking about heating systems. Cold water for me!

shane0007

You are also forgetting that the water supply temperature in the attic may not be 10C but could be higher, so this would lower the ΔT from 45K. The other parameter that will affect the overall performance is if all of the 250 litre of 55C is not used in any particular day, the volume to be heated will vary from day to day. So I would say the COP is probably mid 3.5 on average.

The only true way of monitoring how much exact water an individual house hold is measuring it & living it, comparing what their energy bills were & what they are now. This is sensible.

For comparison reasons, we can only take it from calculations & published tested data from the manufacturer. This, indeed, we do not have for LVP (Energie) system, but I am sure it can be got. The published test data for the NUOS is available & based on the parameters of 250L or 200L per day usage @ 55C & 10C input, we can calculate the running costs within reason for each fuel source. I understand that air temperatures will vary from day to day, but they will for boiler too.

Either way, both the NUOS & LVP may not be for everybody, but IMHO they have earned their right in the market place. For their relatively low initial cost towards systems such as solar thermal, I think they are an excellent choice.
For example, the most common target solar fraction & efficiency is 50:50, giving 50% of your hot water requirements annually. At an installation cost of decent quality systems, sized correctly is on average €5,000. A further running cost to heat the other 50% must be also accounted for. In comparison, the NUOS, installed is circa €3,250 & €3,650 repsectively, but it supplies 100% of the hot water requirements for a running cost of circa €200 per annum. This, as I say has a place in the market. It will not replace other measures, nor is it trying to, but it is a very viable option.

quentingargan

braka wrote: »

How quickly the year has flown! and this LVP/Thermasol/Energie system has worked well. (See attached XL file)

I've used 18cent as an average per KWhr ..cost €208.

As Shane said...winter will be the test for his system .........and I'm looking forward to see how my Energie system compares to his and other new systems during the coming year.

Thanks Braka. Just to put this in perspective, how would you rate your hot water use? I know that sounds like a personal question but would be interested to know roughly if you use a full cylinder each day or less.

braka

quentingargan wrote: »

Thanks Braka. Just to put this in perspective, how would you rate your hot water use? I know that sounds like a personal question but would be interested to know roughly if you use a full cylinder each day or less.

Hi Quintin..,

To be honest I really don't know....I would need a flow meter on the pipe to be sure ...At the moment we are averaging 2.5 units of electricity/day ...showers are in use and the washing machine on the go a few days per week.

Back in Decemeber 2012 (Xmas week) when we had 8 staying for a week the avg was 4/day.
Plenty of washing up /showers and baths and washing machine use as I recall with no complaints.
We don't have a dishwasher..... but washing machine draws water from the hot tap for many of its programmes..

Sorry I can't be more specific.

shane0007

Hi Braka,
I think he meant by number of users on average per day, would you be average hot water demand family, children in home, teenagers with pimples, etc. LOL

It would give a reasonable average for volume per day.

For example, the average person uses approx 45 litres of hot water per day, so a family of 4 would be on average of 180 litres of hot water per day. However, teenagers usually use more.

Power showers also use more. Typically not less than 15 litres per minute but 60:40 ratio between hot & cold. A 10 minute shower would use approx 90 litres of hot, but this ratio would be higher with a lower cylinder temperature.

NIMAN

I would guess that these systems are fairly economical in weather like we have been having the last fortnight?

braka

Oh right....average 3 people (adults) mon-fri and 5 at weekend. 2 out of their teenage years at w/e but probably worse!..
Ordinary shower (good flow though)
I'm always saying we reared the dirtiest kids they wash themselves so much!!.
When we was growing up you wouldn't see a bath for..... (best not go there!!) LOL

shane0007

NIMAN wrote: »

I would guess that these systems are fairly economical in weather like we have been having the last fortnight?

You will find they are not more efficient during hot water. Actually more damaging to the compressor.
I know mine, the efficiency maxes out at 15C air temperature with COP @ 3.7. So no benefit of higher temps. Mine, the maximum allowable air temp is 35C. After that the unit will shut down to protect itself.

whitenoise

Hi Guys,

I want to say thanks for all the valuable information you have posted on this thread and other threads. Myself and my wife have been considering solar panels for some time now, and when recently a leaflet came in the door from a solar panel company we gave them a ring and arranged for the rep to come and see us. After a long information session and explanations of the possiblities of incentives to buy a system from this company. We were a little bit surprised at the cost involved but as this company were offering significant discounts as long as we bought the system from them, right there and then - Sound familiar???
Anyway after paying a deposit once we asserted that there was a 7 day cool off period, the rep left and we started researching what we had just signed up for. It didn't take long to find out that we were being charged about twice what other companies were willing to offer for a similar system. Anyway we cancelled our order and began to research the various options for our DHW needs.

we live in a recently built house with OFCH as the only method of heating water, we don't even have an immersion, the water cylinder is a 200l glass lined tank and it does do a remarkable job of keeping our hot water hot. we have a SSW facing roof, with 2 showers and a large bath. There are 2 adults and 2 young children.

The original company who quoted us offered us a 7.5 msq flat panel system with a 300l tank, other companies offered something similar for about half the price. The original company were fairly disparaging about the competiton say the industry was full of cowboys.

This system or similar can provide us with around 50-70% of our DHW needs over the year and if what I've read on this forum is right, it will cost about €50 in electricity to run the pump on this system, with a service charge between €80 and €200 every 2-4 years. The remainder of our DHW needs will need to be met by either OFCH at a rough cost of about €12/week or electric immersion at a rough cost of about €18/week.


I've been reading this thread with some interest especially with the detsails Braka has uploaded, giving a rough estimate of €4/week to run the thermodynamic system. I had the rep from LVP around lsat night and he gave us a very competitve quote. They seem like a reputable company and from what I've read here and elsewhere people seem quite happy with their systems apart from a few teething problems ie larger esb bills.

This system seems to me to make lots of sense, but again I've only been reading up on this for the lsat 5-6 days.
Would this be a better than a traditional solar setup? or are there pitfalls or other problems that I'm not aware of?

Any info or advice would be greatly appreciated

Thanks

shane0007

Great post. You are certainly right about that company. I could name exactly who you are talking about in an instance. Any company that requires a deposit on the spot without time for the customer to evaluate the information given should be immediately given the boot.

For what you are looking for, IMHO the LVP system will certainly do what it says on the tin & for the costs that Braka is showing.
So if you can comfortably afford the capital cost, I would say go for it.

braka

whitenoise wrote: »

Hi Guys,

................. This system seems to me to make lots of sense, but again I've only been reading up on this for the lsat 5-6 days.
Would this be a better than a traditional solar setup? or are there pitfalls or other problems that I'm not aware of?

Any info or advice would be greatly appreciated

Thanks

As Shane said.... A great post...
it reminds me of a particular Solar Company rep who called on us and started off at €8800 and then cut it by 25% to €6600 for 70% DHW needs.
He tried getting us to sign but we said we would have to think about it.
Imagine my surprise a week later when a girl from the company called to say that the installers would be around the following week to do the job!
We hadn't even signed anything!
I said forget it and don't call again... and then began my quest to find out all I could for a system that would supply DHW 365 days/yr. and so the Thermodynamic system became our choice.

As Shane as pointed out, there are now many alternatives to traditional Solar, (and in my view, these alternative companies don't appear to have the resources of the Solar people companies!)......... so you have choices.

I can only repeat that our family are very happy with the Energie Thermodynamic system thus far....time will tell how it behaves in the years ahead.
Shanes NUOS system (and his feedback on it) will provide further info and no doubt newer systems will be brought to market but to me the investment in Solar does not add up for what you get.

It might be no harm to go and have a look at the alternatives and see them in action...ask LVP for a client who would allow you go and have a look...
We have had numerous callers and don't mind showing them our setup!

To me your OFCH system can be optimised by having a proper service done each year, with replacement of nozzle, etc etc. and Flue Gas Analysis carried out. Upwards of 20% savings can be achieved if carried out by a professional OFTEC technician and the extra you pay for the service is well worth it!

You don't need to run the OFCH this time of the year to get DHW....the Thermodynamic (or equivalent) can look after that at a reasonable cost (mine is €4/wk) but even at twice that its still cheaper than other forms of heating water.
Good luck in your quest and feel free to ask any Q's.

whitenoise

braka wrote: »

To me your OFCH system can be optimised by having a proper service done each year, with replacement of nozzle, etc etc. and Flue Gas Analysis carried out. Upwards of 20% savings can be achieved if carried out by a professional OFTEC technician and the extra you pay for the service is well worth it!

You don't need to run the OFCH this time of the year to get DHW....the Thermodynamic (or equivalent) can look after that at a reasonable cost (mine is €4/wk) but even at twice that its still cheaper than other forms of heating water.
Good luck in your quest and feel free to ask any Q's.

Hi Braka,

One of the things that sparked this whole thing was last December we had our perfectly functioning OFCH boiler serviced by a "Professional OFTEC technician" it was late in december, on the 24th of December the boiler packed in, it didn't seem right to me for the day or 2 after the service, it sounded like there was an airlock in the system as it wouldn't catch. ie it would start and then cutout after a minute. I rang the guy who did the work and between me describing what was happening and his directions he reckoned it was a broken fire valve, I managed to fix it for then, but on new years eve it went altogether, we were stuck with 12 people in the house and no way of heating water - apart from a kettle! the original OFTEC guy was not answering his phone or messages so I managed to get someone else out to have a look. Luckily this new guy was able to fix it. Anyway after this we noticed that the stink of fuel hadn't gone and we seemed to be going through alot of oil, a coupler of weeks went by and it was still the same. I got in touch with the original guy and he came out to have a look at it one day when I was away from home. Anyway hte technician told my wife that there was some part with a crack in it and that luckily he had the part in his van - which he replaced and charged my wife full whack for it, including labour. So all in all a service to our boiler that was to make our boiler more efficient and save us money ended up costing us:

€120 for original service
€50 for 2nd guy to come and fix the broken fire valve
€100 for the original guy to come back and fix the leak.

Now I know that parts break and wear out but the fact that the fire valve and this other part malfunctioned immediately after the service, I know that fire valves can be tempromental things but the 2 things going was a bit too much of a coincidence. Anyway if anyone can recommend a decent boiler, heating system guy in Galway could you PM me the details.

Thanks

whitenoise

PS

It was because of all this that we decided that we needed an alternative to DHW than just the oil

braka

whitenoise wrote: »

So all in all a service to our boiler that was to make our boiler more efficient and save us money ended up costing us:

€120 for original service
€50 for 2nd guy to come and fix the broken fire valve
€100 for the original guy to come back and fix the leak.

Now I know that parts break and wear out but the fact that the fire valve and this other part malfunctioned immediately after the service, I know that fire valves can be tempromental things but the 2 things going was a bit too much of a coincidence. Anyway if anyone can recommend a decent boiler, heating system guy in Galway could you PM me the details.

Thanks

Hi Whitenoise, I am stunned and I feel very annoyed with what happened to you and your family last December.

I don't know what to say...to me there are so many Questions? like...
1. What type of boiler ....condensing/non condensing?
2. What was done for the €120 ? ..it sounds expensive to me!
3. Did you get a report with Flue Gas Analysis results following the 1st service?
etc.etc.

There are so many issues...I'd like to see what the experts on this forum have to say?

whitenoise

Hi Braka,


As far as I know the boiler is a non condensing type
In the service, the technician changed the nozzle, cleaned out the system and he provided me with a detailed flue gas analysis.

Anyway the whole thing left a fairly bitter taste in my mouth.
Currently I'm looking to have some work done on the OFHC system - looking to have an extra radiator to the system as well as a new timer, so if there are any recommendations for someone in the Galway area could you PM me the details.

Thanks

ccsolar

whitenoise wrote: »

Hi Braka,


As far as I know the boiler is a non condensing type
In the service, the technician changed the nozzle, cleaned out the system and he provided me with a detailed flue gas analysis.

Anyway the whole thing left a fairly bitter taste in my mouth.
Currently I'm looking to have some work done on the OFHC system - looking to have an extra radiator to the system as well as a new timer, so if there are any recommendations for someone in the Galway area could you PM me the details.

Thanks

Hi whitenoise
I will pm you details of a very good boiler service guy based in Galway also just to let you know that there are several companies supplying thermodynamic solar panels now , originally LVP had the market to itself but now several companies supply the Energie thermodynamic solar system which it should be known as.
http://www.energie.pt/fotos/documentos/brochura_a4_uk_1321543193.pdf
Cc

deeno1975

Following the lively and informative discussions.

Just a thought, if the Energie (LVP) system was only turned on at certain times of the night and the metering was changed to night rate, wouldn't the cost of running of the system be effectively halved (depending on your suppliers rate). The tank stores 280 litres of hot water so in theory (given 2 to 4 people in a house) this supply should not run out during an average day. The 3 questions I have are;

1. Is there any down side from timing the Energie system to power up at certain times. Would this affect the compressor etc.. my gut feel is not??

2. Will the cold water coming into the tank quickly cool the hot water reserve or over a 12 hour period it wont make much difference??

3. Is the fact that it is now running at night reduce the efficiency or COP gain so in fact the gains from a cheaper electricity rate are offset by running the system at night??

steve82

deeno1975 wrote: »

Following the lively and informative discussions.

Just a thought, if the Energie (LVP) system was only turned on at certain times of the night and the metering was changed to night rate, wouldn't the cost of running of the system be effectively halved (depending on your suppliers rate). The tank stores 280 litres of hot water so in theory (given 2 to 4 people in a house) this supply should not run out during an average day. The 3 questions I have are;

1. Is there any down side from timing the Energie system to power up at certain times. Would this affect the compressor etc.. my gut feel is not??

2. Will the cold water coming into the tank quickly cool the hot water reserve or over a 12 hour period it wont make much difference??

3. Is the fact that it is now running at night reduce the efficiency or COP gain so in fact the gains from a cheaper electricity rate are offset by running the system at night??

Yes there is an advantage to the elec costs by running it at night. The sun aint around, so obviously there will be an inefficiency as the COP will drop. With the reduced night rate electricity, you could be best off just using your immersion for 1 hour to give you hot water. The main issue with these Thermodynamic panels, is that they are effectively competing with an immersion as both consume a decent amount of electricity. LVP claim their 600w compressor driven "system" heats the cylinder in 5-6 hours. A 2500w immersion will do the same in just over 1 hour. Your splitting hairs though an immersion costs €30 and the LVP system costs €5,000. You need to pay off the installation costs of €5k with savings before your getting any "free" energy

shane0007

steve82 wrote: »

Yes there is an advantage to the elec costs by running it at night. The sun aint around, so obviously there will be an inefficiency as the COP will drop. With the reduced night rate electricity, you could be best off just using your immersion for 1 hour to give you hot water. The main issue with these Thermodynamic panels, is that they are effectively competing with an immersion as both consume a decent amount of electricity. LVP claim their 600w compressor driven "system" heats the cylinder in 5-6 hours. A 2500w immersion will do the same in just over 1 hour. Your splitting hairs though an immersion costs €30 and the LVP system costs €5,000. You need to pay off the installation costs of €5k with savings before your getting any "free" energy

Absolute nonsense!
An immersion will not heat 250 litres of water in one hour. Based on the same parameters as a heat pump, (10C to 55C so a delta T of 45C), it would take a 3kw immersion to heat the same volume of water (250 Litres) exactly 261.6 minutes. This equates to 4 hours & 21.6 minutes.

shane0007

For example, here's my upto date running costs for the NUOS.

freddyuk

shane0007 wrote: »

Absolute nonsense!
An immersion will not heat 250 litres of water in one hour. Based on the same parameters as a heat pump, (10C to 55C so a delta T of 45C), it would take a 3kw immersion to heat the same volume of water (250 Litres) exactly 261.6 minutes. This equates to 4 hours & 21.6 minutes.

Absolutely. But you would not heat 250 litres by immersion as you would heat what you needed in a standard cylinder. The Energie system needs a large 250 store to maintain effectiveness. Given the same starting temperature the immersion will not change the law of physics but it can be controlled quite easily and it cost nothing to install. Heating an Energie cylinder from cold I think takes about 8 hours if memory serves. If it is very cold outside it will not even do this. You will need to switch the immersion element on.
If you pre heat your water with solar thermal the immersion can be on for 10 - 20 minutes (3kw standard element) and more than enough hot water for the morning ablutions. The solar thermal has 250 litre store for no cost depending on the weather but the immersion can top it up on a bad day from 35-45c to 50c on average which is not a lot.

shane0007

I don't know about the Energie cylinder but the NUOS heats 50 litres in one hour 10C to 55C. So 200L in 4 hours & 250L in 5 hours.
With modern power showers, hot water usage has increased significantly in years. I have a family of 4, all girls & our hot water consumption is large. With small copper cylinders heated by gas & oil, the cylinder could be reheated a number of times per day so generally it is not noticed but it still costs.
A standard power shower with an internal pump does about 15 litres per minute. Depending on cylinder temperature, this is usually 60:40 ratio hot:cold so a 10 minute shower would be 150 litres with 90 litres of it being from the cylinder.
My point being hot water is usually under estimated & no matter how it is heated, there is a cost. This cost can easily be calculated.

steve82

steve82 wrote: »

Yes there is an advantage to the elec costs by running it at night. The sun aint around, so obviously there will be an inefficiency as the COP will drop. With the reduced night rate electricity, you could be best off just using your immersion for 1 hour to give you hot water. The main issue with these Thermodynamic panels, is that they are effectively competing with an immersion as both consume a decent amount of electricity. LVP claim their 600w compressor driven "system" heats the cylinder in 5-6 hours. A 2500w immersion will do the same in just over 1 hour. Your splitting hairs though an immersion costs €30 and the LVP system costs €5,000. You need to pay off the installation costs of €5k with savings before your getting any "free" energy

Sorry, i should have provided more clarification to what i meant with my post, so apologies on that. I just meant that if a normal family or 3-4 people leaves on an immersion for 1 hour per day, they will have most of their hot water needs take account of. I was also reffering to a 200 liter thermodynamic system. It costs around €0.50 / hr to run an immersion.
Lets say 3 hours of the immersion per day which will definitely be enough hot water for a family of 3-4 - so that's €1.50 per day.
The thermodynamic at 600 w, running for say 6 hours per day costs €0.68 per day, though this will heat 250 litres which is more water. The immersion in 3 hours will heat around 200 litres.
Thats a saving of €0.82 per day.
If the LVP system costs €5,000 to install, that means it will be 6,097 days before the system has even paid for itself, ignoring maintenance. Thats 17 years before you get any "free" energy.
Please correct me if ive made a mistake guys

brophis

steve82 wrote: »

Sorry, i should have provided more clarification to what i meant with my post, so apologies on that. I just meant that if a normal family or 3-4 people leaves on an immersion for 1 hour per day, they will have most of their hot water needs take account of. I was also reffering to a 200 liter thermodynamic system. It costs around €0.50 / hr to run an immersion.
Lets say 3 hours of the immersion per day which will definitely be enough hot water for a family of 3-4 - so that's €1.50 per day.
The thermodynamic at 600 w, running for say 6 hours per day costs €0.68 per day, though this will heat 250 litres which is more water. The immersion in 3 hours will heat around 200 litres.
Thats a saving of €0.82 per day.
If the LVP system costs €5,000 to install, that means it will be 6,097 days before the system has even paid for itself, ignoring maintenance. Thats 17 years before you get any "free" energy.
Please correct me if ive made a mistake guys

I'm of the same view but a critical factor that you haven't allowed for is the increase in energy prices over the 17 years which will reduce the payback period as the savings increase as energy prices go up.

steve82

steve82 wrote: »

Sorry, i should have provided more clarification to what i meant with my post, so apologies on that. I just meant that if a normal family or 3-4 people leaves on an immersion for 1 hour per day, they will have most of their hot water needs take account of. I was also reffering to a 200 liter thermodynamic system. It costs around €0.50 / hr to run an immersion.
Lets say 3 hours of the immersion per day which will definitely be enough hot water for a family of 3-4 - so that's €1.50 per day.
The thermodynamic at 600 w, running for say 6 hours per day costs €0.68 per day, though this will heat 250 litres which is more water. The immersion in 3 hours will heat around 200 litres.
Thats a saving of €0.82 per day.
If the LVP system costs €5,000 to install, that means it will be 6,097 days before the system has even paid for itself, ignoring maintenance. Thats 17 years before you get any "free" energy.
Please correct me if ive made a mistake guys

You've confused me, you have the LVP running for 6hrs, a immersion running for 3 hrs and using that for your maths?

The LVP kicks out 2.9 kw(which can be argued), so your getting pretty much the same stored hot water heated irrespective of the size and your paying for .6 kw with the LVP and not the 3 KW of a immersion.

I'll leave the maths to people cleverer than myself.

steve82

gary71 wrote: »

You've confused me, you have the LVP running for 6hrs, a immersion running for 3 hrs and using that for your maths?

The LVP kicks out 2.9 kw(which can be argued), so your getting pretty much the same stored hot water heated irrespective of the size and your paying for .6 kw with the LVP and not the 3 KW of a immersion.

I'll leave the maths to people cleverer than myself.

Yes, LVP told me that their 590w compressor runs for 6 hrs per day. Irrespective of the output of the unit, it runs for 6 hours at 0.6kw. This is what i used to calculate the running cost of their unit per day.

steve82

steve82 wrote: »

Yes, LVP told me that their 590w compressor runs for 6 hrs per day. Irrespective of the output of the unit, it runs for 6 hours at 0.6kw. This is what i used to calculate the running cost of their unit per day.

I think they made a mistake but I would be guessing. Their device on a good day puts out 2.9kw similar to a immersions 3kw, once the cylinder reaches temperture in a similar time to a normal immersion then there is no need for the compressor to run to heat the cylinder also if no water was used the day before and the cylinder was hot I couldn't see the compressor running to heat a already hot cylinder.

I know nuffing about LVP and if I try to work out the costings I'd just be guessing, (I do have a connection with another product that I'm not trying to promote here:o) i do absolutely think this technology needs to be judged on its figures but real figures which should come from consumers everything else is guess work or sales hype.