Thermodynamic panels WILL or WON’T get the RHI?

Looking at multiple posts on the http://www.greenbuildingforum.co.uk/forum114/comments.php?DiscussionID=9761&page=1#Item_0, discussion, Thermodynamic panels don’t look likely to be a part of the Renewable Heat Incentive payments that are due to start in 2013.

BUT

The 21-09-2012 reply from Jewsons (” the only national builders’ merchant with exclusive rights to the new and innovative Thermodynamic Atmospheric Energy Panels”) to this blog post of theirs, http://blog.jewson.co.uk/2225/were-all-going-thermodynamic

You can find further information at http://www.greenworks.co.uk/. Also, although independent test data is available from Europe and has Solar key mark so is eligible for Renewable heat incentive in the UK, the product is currently gaining independent testing through the BRE in the UK and the data will be available shortly.

suggests they believe Thermodynamic Panels will get the RHI

THEN

From http://www.greenbuildingforum.co.uk/forum114/comments.php?DiscussionID=9761&page=1#Item_22

  1. DECC held a RHI webchat yesterday and, as part of that, confirmed that thermodynamic panels will not be eligible for RHI until they are MCS accredited.
    http://www.decc.gov.uk/en/content/cms/news/rhi_webchat/rhi_webchat.aspx

A users feedback on Thermodynamic Panels

From http://www.greenbuildingforum.co.uk/forum114/comments.php?DiscussionID=9763

We have been in our house for almost a year now, tried to build to passishaus standards and despite plumber, electrician and MVHR installation problems (see previous discussions if clarification needed), the thermodynamic panel is one piece of kit that i cannot fault. There is a backup immersion fitted and has never been switched on and we have had 60 degree hot water every day without fail. I have seen the panel completely white with frost and still no bother with hot water. I am in no shape or form connected to any company that sells or installs the panels, but I have no problem recommending the technology.

Thermodynamic Panels & a heat store or heat recovery system

Looking at one of the Thermodynamic Panel system PDFs:

One set up has a thermal store (a tank that heats up, and your heating is delivered by coils that go into this store, heat up and take that hot water to where you want it), and a second, linked to a pool seems to have a form of heat recover system, in that the colder water from the pool is going back in the loop for re-heating via the Thermodynamic panels and the thermal store tank.

 

For the thermal store the Akvaterm thermal store water tanks looked good at the 2012 Eco Expo in London.

  •  The Akvaterm Akvantti thermal stores are oblong which could be a better shape for the plant room. It’s available as 1400lt, 2000lt or 2400lt volumes. The 1,400 litre unit is £3,757.00 + £85 carriage.

Akvantti-Accumulator-Heat-Store-Tanks-4

 

A chunk more information on the concept and benefits of a thermal store (and their version of one) at http://www.greenspec.co.uk/thermal-storage.php:

Thermal storage – pros & cons

+ Provides effective buffering
+ Reduces boiler cycling
+ Allows for integration with low temp heating systems eg underfloor
+ Adds mains pressure to hot showers
+ Provides potable hot water
+ The use of a heat exchanger means that in most cases, thermal stores can be integrated with existing pressurised boiler circuits
+ Requires much smaller cold water tank then standard vented systems
+ Thermal storage is recognised by NHER software
– Heat can be lost through inefficient heat exchangers
– Storage temperature will usually have to be 10 deg C higher than required DHW temperature
– Cannot be used with existing DHW power showers and pumps
– Expensive and unvented storage, very expensive
– Vented stores require a header tank to be located above the heating systems

Points to consider when specifying a Thermal Store

  • The design of the heating system should be matched to the calculated peak heat load.
  • When including solar heating, ensure that there is extra capacity within the store to accommodate fluctuations.
  • Where a biomass boiler is being used, consider sizing the store to provide for the heat capacity generated in a load / firing
  • Consider designing not only for short-term anticipated capacity but possible future extensions to the system.
  • Consider stratification of water temperatures within the store, particularly where low-grade heating is provided. Effective separation between the hot water at the top of the tank and the cooler water at the bottom, can increase the time between charges.
  • Ensure that there is adequate insulation to the store (100mm + PU foam)
  • Ensure that there is adequate pipework insulation

 

Some more Thermodynamic panel info

From a discussion on http://www.greenbuildingforum.co.uk/forum114/comments.php?DiscussionID=9511&page=1#Item_15

Gary

I consider these as a form of air source heat pump, without a fan or finned coils. The underlying technology is well established and should be as reliable as a GSHP.

The panels are a good solution for a marine environment – I wouldn’t use ASHP units near the sea as the coils rot after about 7 years due to salt corrosion, so they would be a cheaper alternative than GSHP for such areas.

I have seen a completed installation and the owners were very happy with it.

Solar thermal it ain’t however – there is an improvement in COP when the sun is shining but it won’t provide free energy.

Chris

As far as I can find there are two manufacturers of these systems, the best known being Energie in Portugal http://www.energie.pt/ but also a company called Energy Panel in Spain. http://www.energypanel.es/productos.aspx?idFamilia=1&idProducto=1

The problem I have with them is a seeming lack of independent verification of their claims for running costs. I’ve seen mention of various installations being independently monitored but all my previous efforts to get these reports have so far failed.

Does anyone know of any such independent verification?

Some updated Thermodynamic heating system info

I’ve come across the GreenServeUK website with new info on the Thermodynamic Panels.

There’s a big FAQ at http://www.greenserveuk.com/faq/

How it works from http://www.greenserveuk.com/thermodynamics/how-they-work/

Step One

The environmentally friendly refrigerant liquid is fed into the veins of the solar collector.

This refrigerant (R134A) has a boiling temperature of -25°C. The panel absorbs the heat from the environment and raises the temperature of the refrigerant.

The liquid absorbs the heat and it vaporises into a gas which increases the pressure.

Thermodynamic Panel Dimensions are h 800mm, l 2000mm, D 20m.
Each panel is about 8 kg.

Step Two

The hot gas is then passed through a compressor where the pressure causes it to heat further.

Step Three

The heated gas is then passed into the heat exchanger where the heat is transferred into the water cylinder.

Step Four

The cooling gas then passes through a valve reverting back into a liquid where it runs back into the panel where the process begins again.

The system is a solar domestic hot water system in which the solar loop operates on a similar principle of a heat pump.

It is composed of:-

  • An unglazed heat absorber  (1) with 3.20 m2 total aperture area.
  • An insulated,  hot water thermal store (200 l) (2)
  • A  thermoblock, which comprises the electrical powered compressor (5), the thermostatic expansion valve (7), the electrical heating element (4) and the controller.
  • Heat transfer fluid (refrigerant R134a)

The heat transfer fluid in the solar loop is the refrigerant R134a.

The refrigerant is passing through the absorber and evaporates while collecting energy from the surroundings.

The evaporated refrigerant is sucked by the compressor which raises the pressure.

In the condenser, which is integrated as an immersed solar-loop heat exchanger in the lower part of the store, the refrigerant condenses while transferring its condensing heat to the domestic water in the store.

Before the refrigerant is returning to the absorber, a thermostatic expansion valve is reducing the pressure.

An electrical heating element is located in the lower part of the store at the height of the solar-loop heat for use in emergencies and for the anti-legionnaires system.

The magnesium anode (8) or sacrificial anode will extend the life of the tank.

 

Thermodynamic installed at Maidstone UTD Football Club

Just got this press release:

Thermodynamic installed at Maidstone UTD FC…
Project: Maidstone United Football Club – Gallagher Stadium
Client: Graham
Contractor: Gallagher / Greenheat

Thermogroup UK recently supplied two Thermodynamic systems, an Eco 2000 and an SB 24 to meet 100% of the hot water demand for showers and underfloor heating at the new home of Maidstone United FC.

MUFC were attracted to Thermodynamic because of the environmental factor and the potential savings possible against the originally specified electric heating system.

Thermodynamic panels at maidstone united

 

It was estimated that a 24 panel system, to provide underfloor heating to the clubhouse, would use a minimum load of 4.2kW of electricity. Based on this figure and assuming the system is used for an average of 5 hours a day, it is estimated that the SB 24 at MUFC will cost £2.10 per day or £766 per year to run (at £0.10/kW per hour).

The SB24 at MUFC is expected to have a payback of around 5.5 years and bring about an annual saving of £3000 when compared to the electric system that was originally specified.

Please note: The figures in this email are estimates only and we are in the process of installing energy monitors at MUFC to track the exact running costs, savings and payback period.

Thanks for taking the time to read this email and look out for the next Hot News delivered to your inbox. Please consider adding this email address to your safe senders list to ensure you receive all of our communications.

Hot Water Heat Recovery Options

It looks like there is a new player in the UK market. OR one that I’d not previously spotted!

They have a good few shower tray / under shower options and those that can be more centrally integrated into your whole property hot water system.

From http://www.recoupenergysolutions.co.uk/our-range/recoup-retrofit/:

Our most popular waste water heat recovery system due to it’s great efficiencies, low price and superb all round performance. Ideal for new build applications, this product is sure to deliver results, whatever your criteria.


Recoup Tray+

Our tray is the perfect solution for apartments or ground floor en-suites. Achieving code in city apartments without renewables is notoriously difficult; this shower heat recovery system with flexible tray size is the answer that doesn’t cost the earth.

Building a wet room or have access issues? The Recoup Drain+ provides a great option. Finished in stainless steel and offering 50% efficiencies, this is a must have system for your self build or walk-in shower.

This compact WWHRS is easy to install, easy on the pocket and easy to maintain! As it’s name suggests, it’s ideal for retro-fitting in domestic and commercial properties. A very cost effective way to achieve efficiencies of up to 22%.

A system with great efficiencies specifically designed for large developments with good water pressure. This single walled exchanger provides up to 68% efficiency, so will tick a box for the Technical Director or architect looking for a cost effective solution to achieve code.

Solar Panel Feed In Tariff Update (FIT)

From http://www.building4change.com/page.jsp?id=1305

The tariff for a small domestic solar installation will be 16p per kilowatt hour, down from 21p, and will decrease on a three-month basis thereafter, with pauses if the market slows. All tariffs will continue to be index-linked in line with the retail price index (RPI) and the export tariff will be increased from 3.2p to 4.5p. The new tariffs are expected to give a return on investment (ROIs) of more than 6 percent for most installations, and up to 8 percent for the larger bands.

The scheme lifetime will be reduced from 25 years to 20 years for new solar installations.

FIT changes

  • Tariffs for solar PV installations from 1 August to be 16p/kWh for household scale solar PV installations. Tariffs for larger installations are also to be reduced
  • Multi installation tariff will be increased to 90 percent of standard tariff. Organisations with more than 25 PV installations will get 90 percent of the standard applicable tariff, increased from 80 percent
  • Average tariff reductions of 3.5 percent every three months. Reductions will be bigger (up to 28 percent) if there is rapid uptake.
  • Tariff cuts will be skipped (for up to two quarters) if uptake is low. Uptake in three different bands (domestic (size 0-10kW), small commercial (10-50kW) and large commercial (above 50kW and standalone installations) will determine the quarterly reductions within those bands.

UK Solar Hot Water Trial Findings

The Energy Saving Trust did a survery on a large number of UK and Republic of Ireland solar hot water systems.

PDF report on the survey >>

Key Points

  • There were 54 flat-plate systems in the trial.
  • There were 34 evacuated-tube systems in the trial.
    • There was no difference in the annual solar energy yield observed between solar installations using flat-plate solar collectors and those using evacuated-tube solar collectors. This may be because although evacuated-tube collectors have higher insulation, flat-plate solar collectors generally have a larger working area as a proportion of the collector size.
So there are none of the “new” Thermodynamic Panels in the survey. These do appear to be different and better. Providing 24 hour hot water.

Distribution of the surveyed / trial locations:

So for Silver Spray in Cornwall, should get better results as more sunshine:

The solar energy input to the hot water cylinder is at a maximum in summer, with back-up heating providing more energy in the winter months.

It’s key to set the backup (non solar) heating system to run so that the solar heating can be most effective and the house occupants have hot water when desired.

How to improve the performance of a solar water heating system:

  • Using boiler timers and/or solar controllers to ensure that water is only heated by the back-up heating sources after the water has been heated to the maximum extent possible by the sun.
    • Timing of back-up heating and hot water use. Systems
      provided more energy when the back-up heating was
      used just before the main hot water use or at the end of
      the day. This provides a better opportunity for the solar
      collector to heat the water rather than using the back-up.
  • Having an adequately sized dedicated solar volume (that is, a portion that can only be heated by the solar water heating system). Where a dedicated solar volume is not used (for example in systems that do not require the existing cylinder to be changed), the timing of back-up heating has a particularly important impact on performance.
  • Insulation is a vital part of this, as systems with poorly insulated storage cylinders can suffer from inadequate hot water provision in the mornings.

Key Findings:

  • Well installed and properly used systems can provide around 60% of the years hot water.
    • Across the whole trial, the proportion of domestic hot water energy provided by solar power ranged between 9 per cent and 98 per cent (with a median of 39 per cent).
  • Plenty of other findings, see the report.

Customer / Consumer Advice

What to expect from your installer:

  • All MCS installers should be able to provide a detailed breakdown of the specification and costs of their proposed system. They should:
    • Complete a technical survey.
    • Explain how they calculated the size of the system to be appropriate for your hot water usage.
    • Provide an estimate of how much heat will be produced by any proposed system.
    • Supply clear, easy-to-understand and detailed information and advice on how best to use the system and operating instructions.
    • Explain how the system will be installed and if there will be any disruption to your property.
    • Install and set controls and settings to ensure you get the most out of your solar water heating system.
    • Provide clear and easy-to-understand information on product and workmanship warranties.