This page contains a Flash digital edition of a book.
HVAC SYSTEMS


n Supply temperature n Return temperature


60 85 90


n Supply temperature n Return temperature


50


80


75 40 70 30 65


20


60


0h


83d 8h


166d 16h Time (s)


Heat pump plans still ‘very much on the table’


“I would emphasise,” the Trust’s director of Specialist Services added, “that the heat pump proposal is far from off the table; there is a really exciting opportunity for that project, but let’s get our existing system fully optimised first, because taking a 14 per cent carbon reduction from a heat pump, when we can have the same reduction from reconfiguring the system at a fraction of the cost, seems eminently sensible.”


John Henry explained that as soon as the Trust can get the work tendered and prices back, he would like to get the scheme under way. He added: “We are currently out for a measured term contract for mechanical and electrical contractors, and if the work could be undertaken by them it would save considerable time on tendering and procurement.”


Chris Davis added: “This is where the advantages of delivering the design intent at the contractor installation stage comes in. Effectively, the piece of work we did for John was in two stages – firstly conceptual, where we looked at the various options for the Trust to consider, and it has now chosen a path. In the second stage, Hysopt has delivered the detailed engineering, which provides the digital twin for the contractor to pick up, install, and commission against.


Sharing the digital model with the contractor


“When the Trust appoints a contractor,” he continued, “John and his team will be able to share the digital model with it, but as part of the output, the Hysopt software also models all the valve and pump selections. Typically,” he continued,


78 Health Estate Journal September 2020


250d 0h


333d h


0h


83d 8h


166d 16h Time (s) Figure 3: Operating temperature of the heating installation (left: current operation; right, after optimisation).


“it is left to the contractor to make such decisions, and they will often size the components based on a rule-of-thumb. However the valve and pump selection is very much an iterative process, with every component interdependent on the others. While nobody can undertake the thousands of calculations required manually, the software does all this, and will give John a schedule and specification of all the pumps and control and balancing valves required, and where they will fit within the system. His contractors can then procure and price against this specifically, but will also have the commissioning data, such as the kV values for all the valves provided. The installer can thus commission the equipment accurately, rather than having to spend considerable time on site doing the work by trial and error, such is the iterative nature of the commissioning process. This is all part of the tender information that John has. All he has to decide now is whether he wants product specifications, or the name of specific manufacturers and models of, for example, control valve.”


Putting the client back in control John Henry said: “What this work with Hysopt and its software has done is put us back in control of our design and commissioning, and in my view Trusts need to reclaim the informed client role – something that has tended to slip in recent years. I first learned about the Hysopt software at IHEEM’s Healthcare Estates 2019 event in Manchester last October. On visiting the company’s stand, I saw a demonstration, and decided this was the sort of solution we needed.” Chris Davis added, as our discussions neared their conclusion: “What John has just said about the Hysopt software


putting the client back in control is fundamental to how we operate. Often the client ends up paying the bill, is strong-armed into using whichever solutions are suggested most vocally by the consultants and the contractors, and may then end up having to sort out all the challenges and underperformance after the chosen system fails to deliver as expected. The whole point of the transparency offered through our software is indeed about putting the client back in control of the process, and giving it transparency over what it is going to get. It also enables say, an NHS Trust, to hold its supply chain to account. It’s no longer just about reputation, relationship, and price, but rather about real-world performance, and enabling, for example, a Trust Board to best balance capital and operational costs, so that they can go out and make the best fact-based specification decision.”


In conclusion


“The NHS has a significant role to play in helping the UK meet its net-zero carbon objectives and the decarbonisation of heat across NHS estates remains a huge challenge,” Chris Davis added. “With the recent Government announcements around investment in public sector decarbonisation, alongside the ambitious Healthcare Improvement Programme which plans to construct 40 new hospitals over the coming 10 years, there is significant opportunity for NHS Trusts to follow the lead set by Mid and South Essex in adopting HVAC digital twin technologies to help ensure that the right choices are made, and that the integrity of optimised system design is protected into the installation and commissioning stages.”


250d 0h


333d h


hej


Temperature (˚C)


Temperature (˚C)


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92