A better way for retro fits than common flat panel installs

[stuartiannaylor]

Well if you look at electricity generators aka power stations you could argue that they are not. Heat stations is a more accurate term is it 60% heat ? Anyway looking at this and prob unfortunately in lower latitudes.
Heat is hard to transfer and thats why we end up with huge electric power stations. This could change as we could have many small scale CHP units supplying local heat whilst supplying electricity to the grid.
It all depends on how you look at things I find lime juice very effective in changing that.

Stuart

[renewablejohn]

Micro CHP is ideal for providing domestic hot water and central heating as its the waste heat from the steam cycle which has to be dissipated to make the steam cycle efficient. These panels with a micro CHP could make your photo voltaics worthless as you would be able to claim Fits on both the generation and the renewable heat. It could also displace the thermal solar market because why would you want heat when you could have both heat and power.

[martin]

But is it going to do it in midwinter (when it's most needed), and in the average urban situation? Do I take it that it will also be completely silent, vibration-free and only cost threepence halfpenny?

[renewablejohn]

But is it going to do it in midwinter (when it's most needed), and in the average urban situation? Do I take it that it will also be completely silent, vibration-free and only cost threepence halfpenny?

Probably not going to do it in midwinter but the beauty about thermal oil is it does not care less how it is heated so the thermal oil could also be heated by Biomass. I have permission to use a Dunsley Yorkshire boiler for this purpose linked into solar panels to generate electric and run the central heating and hot water. As for silent not quite as you need several central heating pumps for circulating the thermal oil and water circuits.

[stuartiannaylor]

Thermal oil, no it definately isn't vegtable oil as that has various negative properties. A quick google will take you onto various links. I don't think I would like to heat vegatable oil or diesel to temperatures that range from -70°C to 400°C. There are many different types for various purposes and mineral oil specifically formulated for the purpose is very common.
This is used inplace of your glycol loop and its reason is temperature range and yes its specific heat capacity is about half that of water but also it can reach temperature difference of four times as much.
Most large scale solar farms in operation generating mega watts of power currently use thermal oil in the heat exchanger loop. The reason is the extended working temperature range as that has various advantages.
As for cost, leaks, refilling its the same as a glycol loop just hotter.

Martin if it is designed as a hybrid system to capture and run CHP and generate up to 30kW during peaks months and during low capture months provide 100% DHW then yes. There is a sterling engine solution on the market called Whispergen so as to being quiet and vibration free. I guess it could be as it depends on design. As for only cost threepence halfpenny, well at least I will try and show some courtesy to questions of that level. Does anything cost so little as that nowadays apart from the quality of your questions Only joking but really Martin Silent, Vibration-free and only cost threepence whats that on about apart from sour grapes for a reason I have no idea?

[martin]

Please try to understand the distinction between "sour grapes" and a very real belief that something is "pie in the sky" in practical terms now - if we are to apply this "invention" we have to firstly understand how it works, what it can actually achieve, and where it may fit into the grand scheme of things....... As an example, some years ago we heard of developments such as this in the field of pvs, that would allow ludicrously cheap panels, and the ability to "paint" surfaces with them - good, valid research, with something that sounds entirely feasible (just a reworking of a current technology)-  but several years down the line, we're still waiting....
What you may take as flippant comments about halfpennies are actually backed by sound common sense - for a technology to be used "in public" it has to work, it also has to "user friendly" (no such thing as completely silent gennies outside research labs), and it has to be affordable. I would also add that it should repay it's embodied energy in short order, or there's little point  in it......

I think RJ shows an understanding of the potential shortcomings - however efficient it is, it almost definitely won't give full DHW in the depths of winter without simply colossal and impractical arrays, that will fall at the hurdle of roof space and affordability (as do similar plans involving existing technologies).......

[renewablejohn]

the beauty about thermal oil is it does not care less how it is heated so the thermal oil could also be heated by Biomass. I have permission to use a Dunsley Yorkshire boiler for this purpose linked into solar panels to generate electric and run the central heating and hot water. As for silent not quite as you need several central heating pumps for circulating the thermal oil and water circuits.

So what exactly is the thermal oil...? Is this cooking oil? Diesel or something else. I wondered over a year ago about having a thermal battery of oil, or PCM fluid, but when the thing is fully thought through (leaks, refilling, cost, relative thermal capacity etc) it didnt make sense.

Thermal oil is what the process industry uses on a daily basis from baking bread to producing safe steam.  Depending on what temperature you require depends on what sort of thermal oil you use. The main advantage over steam is that you get the temperature you require without the dangers of being pressurised. Even so an oil leak at 230C cooks your body very quickly.

[stuartiannaylor]

Hi Martin, I have enjoyed the banter and I understand that sometimes you have to agree to dissagree. Its just my manner of working I have, probably due to my profession of a process and control engineer for high throughput products. Strangely quite a few bakeries British bakeries, Allied ... I am from Lancashire so please the "inta bread" thing has been done to death.

I have a little bit of inheritance and I have never been a conventual type. I also know that a prototype can cost huge ammounts of money. But I have seen that if there is the will, then the automation of that product can produce, vast cost reduction, if you get the throughput.
Now I am not saying I am going to purchase a CERN flatty, sterling or steam turbine. I do admit, I am watching eagerly and I might, and I know it will be purely an experiment prob a complete waste of time. It will be worth it though as I get on great with the nieghbours and I can see there expression's "Oh god what is he at this time". It will be worth it for that and the ribbing in the local pub.

I am thinking in terms of a hybrid that can generate during "peak sun" and at others times 100% solar DHW. The CERN plate is of interest as the current three metre monsters capture a serious ammount of energy. They do have capture densities that make possibilities that no other product currently does. I hope they do make a domestic product otherwise it might be time to don a balaclava and head for a test site in spain

[dhaslam]

There are a couple of things you would need to make it a viable project.   The first would be  a way of rotating the panel to keep the sun focussed on the panel,  with accurate  direction control you could use a fresnel  lens to intensify the sun.    An alternative would be  multiple panels that  are used in  turn as  the  final temperature  boost.      The other thing would be a way to store  the excess heat in summer.   The very high temperatures would mean that   would high enough output temperature  from storage  for heating and DHW all year round. 

It would have to be grid connected  because electricity generation would be fairly sporadic, only during the  middle part of the day  and only on sunny days   but the output could be quite  high.     Automation would be quite tricky, with such high temperatures involved normal valves wouldn't cope.   

[renewablejohn]

    The other thing would be a way to store  the excess heat in summer.   The very high temperatures would mean that   would high enough output temperature  from storage  for heating and DHW all year round. 

It would have to be grid connected  because electricity generation would be fairly sporadic, only during the  middle part of the day  and only on sunny days   but the output could be quite  high.     Automation would be quite tricky, with such high temperatures involved normal valves wouldn't cope.   

Excess heat can easily be stored in standard Asphalt shipping containers which are designed to be heated by thermal oil.
It would not need to be grid connected as the thermal oil steam evaporator is set up to produce steam on demand therefore electric could be produced on demand.
Automation would not be a problem as all normal valves and pumps are available in thermal oil specs because they have been used in industry for decades.