Nutech solar enhanced heating & hot water

NuTech’s Solar Enhanced Heating and Hot Water System allows Developers to meet the requirements of TGD L 2011 in a single simple package using standard construction methods This system can QUADRUPLE the amount of solar energy actually delivered to the house when compared to a standard Solar Water Heater. It uses an enlarged array of solar collectors that feeds all of the solar energy to both the hot water cylinder / solar store and to solar space heating by way of a dedicated fan coil radiator

Solar Enhanced Heating & Hot Water Enlarged Solar Array collects free energy

Fan Coil Radiator heats House by way of energy from the solar array

Heats Hot Water Cylinder

The array of solar collectors feeds energy by way of the solar fluid into the coil at the bottom of the hot water cylinder. This will occur all year round.

In Autumn, Winter and Spring the solar fluid is also pumped to a fan coil radiator which is placed generally in the landing area.

The fan coil radiator delivers the heat from the collectors directly to the house The cylinder also acts as a solar store such that solar heat can be delivered to the house by way of the fan coil radiator in the evening and at night.

Consumer Display unit Computer controlled

The whole system is controlled by the specially developed NuTech Intelligent Renewable Energy System controller.

This highly cost-effective system allows energy from the solar array to not alone heat the hot water cylinder but also to feed heat directly to the house using the fan coil radiator when required.

This Renewable Energy System can deliver increased amounts of solar energy to the house and greatly aids the designer in achieving compliance with TGD Part L of the 2011 Building Regulations. The whole system is controlled by way of NuTech’s Intelligent Renewable Energy System (IRES) controller The system relies on NuTech’s sophisticated IRES controller to act effectively. Without the IRES controller it would not be possible to collect the low levels of solar radiation which we experience in Ireland in winter. It is important to note the system can deliver solar energy to the hot water cylinder and the fan coil radiator OR just to the fan coil radiator in times when the weather is duller. In summer the system will deliver solar energy to the hot water cylinder only as no heat is generally required in the house.

During the night solar energy which was collected by day and stored in the Solar Heat Storage Cylinder is fed back into the fan coil radiator to further reduce energy required for home heating. The amount of solar energy stored is a function of the size of the array, the size of the tank and the amount of solar energy received on a particular day.

This Solar Enhanced Hot Water and Space Heating system can in effect quadruple the Renewable Energy Contribution by way of the solar array to the house. This added Renewable Energy to space heating is also recognised in SEAI’s DEAP procedure by way of Appendix Q when calculating the BER of the house.

With this system NuTech can meet all the requirements of TGD L 2011 by way of a single package using standard construction methods and using easily achievable U-Values in the ground floor, external walls, roof and windows

The Intelligent Renewable Energy System (IRES) controller This unit, which is an essential part of the IRES, gives real time information on how the system is performing at any time.

Figure 1:

The Homeowner’s Display Unit

The display above is showing that the system is in the ‘Solar to Water and Ventilation’ mode. This means that it is heating the Hot Water Cylinder and the air in the house by way of the Fan Coil Radiator.

It also gives the outside air temperature, temperature of the house, temperatures in the top and bottom of the Hot Water Cylinder and the temperature of the air being delivered to the house.

As mentioned previously without the IRES controller it would not be possible to collect the level of solar energy as this system does. Nor would it be possible to achieve the comfort levels which this system delivers by varying fan speeds to deliver the Positive Input Ventilation air.

The Pumping Station The Pumping Station incorporates the motorised valves which are pre-plumbed and pre-wired Figure 2: The Pumping Station

System operation on a sunny winter’s day Figure 3 below shows a schematic of the system in operation on a sunny day in winter. Warm water from the collector is fed to the hot water cylinder by way of the lower solar coil in the cylinder. The water is then pumped to the Fan Coil Radiator and thereby delivers heat directly to the house.

Figure 3

It should be noted also that when in this mode the efficiency of the solar array was found to be improved by 10% over a standard equal size solar water heating system ( report by University of Ulster).

Operation of the system on a cloudy winter’s day Figure 4 below shows a schematic of the system in operation on a cloudy day in winter. Water from the collector can be heated to 30°C under these conditions depending on the depth of the cloud cover. This water is most likely too cool to be fed to the cylinder but by pumping it directly to the Fan Coil Radiator it delivers heat at approximately 28ºC to the house. Typically this can continue on this type of day throughout the whole of daylight hours. This holds the efficiency of the solar array at a high level when a typical Solar Water Heater would not be operating at all under these conditions.

Figure 4

Evening time during the heating season There is the ability within the system to store solar energy if and when a bright sunny day occurs. This is important in modern low energy houses.

During the evening time the water is pumped from the cylinder coil to the Fan Coil Radiator which will deliver heat to the house. This again further increases the amount of ‘free’ energy delivered by the system to the house i.e. stored solar energy is delivered to the house in the evening.

Figure 5