GNCE – the sustainable design specialist

11 Feb , 2019  

Glenn Nunan, principle of Glenn Nunan Consulting Engineers (GNCE), was shortlisted for the Designer of the Year award at this year’s Irish Construction Industry Awards. Building Ireland touched base with the innovative, industry-leading Dublin-based Chartered Engineer, who pioneers the application of low energy technologies in the production of truly sustainable buildings.

Boasting over 20 years’ experience covering a broad spectrum of roles and responsibilities in the construction industry, Glenn Nunan established Glenn Nunan Consulting Engineers (GNCE) in 2010 to provide a range of Engineering based Consultancy Services.

GNCE are Consulting Engineers based in Dublin 2. Their service is based on Glenn extensive experience and reputation built over many years in the construction industry. As well as Mechanical, Electrical & Sustainable Design Solutions, other services offered include IT, AV, Security, Lighting & Lift Design, Building Energy Modelling, M&E Cost Control/Management & Value Engineering, Expert Witness & Legal Dispute Advice, CAD Services & 3D Revit Modelling, Acquisition/Condition Surveys & Reporting.

The eponymous Managing Director is particularly interested in sustainability, including the application technologies such as Geothermally fed Heat Pumps. He holds a Bachelor of Science in Engineering honours degree from Trinity College Dublin as well as a Diploma in Engineering from Dublin Institute of Technology, where Building Services Engineering was studied in Bolton Street.

Some Key Recent Projects include: The Iveagh Garden Hotel at 72 -74 Harcourt Street, Dublin 2, a project which consisted of the conversion of an existing 5,200m² commercial building (previously a bank) with façade built in the Georgian style into a 150-bedroom, 4-star hotel over an 18-month period.  This involved the recycling and reuse of the current concrete frame building, four storeys over lower ground and basement levels which was extended over a further two floors with a lightweight steel structure.

The building energy centre was excavated below basement level to accommodate all the main plant and equipment. This SEAI EXEED rated building is a combination of high performance systems and building fabric improvements resulting in energy and carbon reductions in excess of 80% and innovate applied proven technologies yielding system efficiencies in the range of 800-900%. The next Phase of the Project involving the renovation and conversion of 71 Harcourt Street, is currently underway.

Meanwhile, the well-renowned Monasterboice Inn, Silloge, Drogheda Road, County Louth needed additional function room facilities that were required to be built in an energy-efficient and low running cost manner. The 380m² function room facilities were newly built to a very high standard and elements of the existing facility refurbished and modernised.

The low energy systems employed utilised the on-site river as an energy collector via water and air source heat pumps to provide heating and cooling to the building and when combined with the building fabric resulted in an A Rated building which has achieved SEAI EXEED certification. The next Phase of this project the addition of a 1000m2 new build 23 Bedroom Accommodation Wings is at design stage.

The newly built St. Agnes Primary Care Centre in Crumlin, Dublin 12 comprised 2,600m² over three floors, consisting of two floors of HSE medical practice and support departments with a private GP facility, pharmacy and cafeteria located on the ground floor. While the building is A Rated as required by the HSE, it also meets nZEB targets due to the design approach having been adopted. All the building heating requirements are catered for by roof-mounted air source heat pumps which when combined with heat recovery ventilation via thermal wheels has led to a highly efficient building. Phase 2 of the St. Agnes Site, 103 Independent Living Units over 6 Blocks is currently under construction.

Many of the low energy design approaches that have been applied to these projects required additional capital funding which was achieved by a combination of economic life cycle payback and support and funding from SEAI under the EXEED program to assist in financing the extra over costs involved.

The final result of the above projects was only achievable due to a strong team effort and an organic collaborative endeavour which is at the heart of the design approach which has been adopted.

While all of these projects featured innovative elements, the main highlight was the combination of the sum of the parts of the building in achieving exceptionally high efficiencies, which is most notable in The Iveagh Garden Hotel where system efficiencies in the range of 800 – 900% have been achieved.

Another notable project completed from a strong portfolio of innovative jobs was the refurbishment of a 2,500 m2, five-storey office building in Dublin City Centre to form the HQ for the Pharmaceutical Society of Ireland (PSI). Here, the design team were engaged to provide a headquarters building for the Pharmaceutical Regulator within an existing speculative office building constructed in 1992.

The project included the entire strip out, refurbishment and fit-out for a bespoke headquarters whilst also retrofitting state-of-the-art sustainable mechanical and electrical designs, to achieve a bespoke sustainable building

Mechanical & Electrical Design low energy systems included A/C – Active VAV Chilled Beams c/w CO2 monitoring, VSD’s on AHU’s and Pumps feeding 2-port systems, Dry Air Coolers and integration of lighting controls, security, energy monitoring and other systems.

Simply put, GNCE do things better…  “We apply the technology in an appropriate manner, based on sound engineering,” notes Glenn. “Some of our best projects have been renovations and it’s only in the last few years that the new-build market has been coming back again.

“For PSI House, we worked closely with the Pharmaceutical Society of Ireland on a complete refurb, renovation and fit-out which had to be completed within a 14-week programme on budget using proven technology, appropriately applied to create a sustainable, low-energy system.

“A building is not a single part but the sum of all the parts which achieves the desired total. This is a very important part of the design approach. As a designer, everybody on the project has to work together to make the building, as a system, work successfully.”

It would be no exaggeration to suggest that GNCE’s work at The Iveagh Garden Hotel was exceptional. “Every working part of that building was replaced, all components are brand-new.

“Clients are looking for low running costs and easy maintenance and we work with them to achieve this. As a team, we were able to achieve an 80% reduction in energy use and carbon at Iveagh Garden by applying appropriate technology that suited a hotel application.

“We installed a combined heat and power (CHP) plant for low cost highly efficient onsite electricity generation. Heat harvested from the CHP’s Engine and Flue means that the hotel can have all its hot water for showers for free. We knew there was a well with water from an underground river on site which when tested had a high yield that meant we had hit oil in water energy terms. Passing this water through a Geothermal Heat Pump generates the hotels heating at an efficiency of 500-600% with all the hotels cooling being provided virtually for free.

“Normally, with a heat pump when you are heating you reject cooling and vice-versa, like in a domestic fridge where it cold inside and you reject the heat at the back, however, we don’t throw the by-product away and instead its captures in a vessel and used.

“We drive the heat pump with electricity generated on site while harvesting the high temperature waste heat for use in showers and also capturing the waste from the heat pump– heat if we’re generating cooling, or cooling if we’re generating heat – so you have a system that doesn’t waste and results high system efficiencies. While it is a simple concept, the devil is always in the detail.

“Highly efficient technologies such as heat pumps with efficiencies ranging between 400-600% (bearing in mind the best boiler is 99% efficient on the day you install it) when run 247 utilise electricity at night time when demand is low. It’s going to take a few years to have these technologies as standard in Ireland so that we have the capacity to take advantage of other renewable technologies such as wind energy generated at night.”

Why isn’t everybody using these technologies? “You have to understand the technology to apply it appropriately. When I was a student at Bolton Street, I couldn’t understand why heat pumps weren’t everywhere. Now that greener technology is here and has been accepted, our countries stock of systems will have to catch up to take advantage of it other technologies like wind energy generated at night time.

Remember, there was a time when electricity was seen as a dirty fuel in this country, which of course it isn’t when generated renewably. While a lot of the technologies aren’t new the advantages are greater now that they are more affordable – but Ireland needs to stock up.

“A lot of these concepts are very obvious and that’s why we’ve always managed to apply low-energy, high-efficient technologies in our projects, even during the dark days of the recession. A building is like a body and all the limbs have to work together for it to function effectively. Every building is a system in itself and each part is a contributor to that system.

“These systems are available to any client who has the foresight to implement them based on the right advice. You need space, because your large vessels (to put the heat/cooling energy in) are effectively your batteries. A lot of what happened at The Iveagh Garden was subterranean, a large plant room was excavated beneath the ground to accommodate the large 5000 litre High, Medium and Low Temperature Vessels. What we’re doing is obvious and quite simple, really.”

I put it to Glenn that it is only simple if you have a mind like his, but perhaps not nearly so straightforward to the rest of us… “I suppose it helps if you have an interest in it and a passion for it,” he concludes.

Glenn Nunan Consulting Engineers (GNCE),

16 Merrion Row,

Dublin 2,

D02 CF90.

Tel: 0 1 602 0678

Email: [email protected]

Web: gnce.ie

Taken from Building Ireland Magazine, October 2018, Vol 4 No 9