Iveagh Garden Hotel

72 Harcourt Street, Dublin 2

The Project

Ochsner Engineering are delighted to announce Seai Green Energy awards have short listed this project in the Sustainable Energy Achievement Award category.

The Iveagh Garden Hotel development planned to construct a unique low energy hotel in the heart of Dublin that is Based on a love for nature and the natural surroundings.

Transforming an existing bank building into a fully functioning hotel by reducing the impact of the hotel on the environment despite the intensive use of Energy required in catering for over 500 people was an enormous challenge.


The development team lead by Brian Mc Gill and his son Barney set a target to create the lowest carbon footprint possible for the Iveagh Garden when compared to any hotel in Europe despite the building being ‘40 year’ old. This decision would require removing the refurbished heating and plumbing system from the building which ran on fossil fuel and replace it with a system to use natural energy and smart concepts. A costly decision, but in the words of the owner ‘you cannot put a value on nature, it’s the most important asset we have and I want to use it’



The entire heating, cooling and hot water systems were removed from the building and a development plan agreed that would raise the bar on every existing standard that is energy related beyond best practice to create a solution to fit the concepts of EXEED.

While this plan would add millions to the renovation cost, natural energy at zero cost would repay the loan with a fast return on investment.

The government energy agency Seai got behind the initiative offering financial support on the precondition of performance testing when operational so that the system could become a flagship for new development.

Standards were raised, new methods were developed and energy performance was interlinked with consumption by simply exchanging energy to areas in need from areas in excess, the energy exchange system applied takes renewable energy and low carbon design to a whole new level.

To insure nothing gets wasted, the energy transport network through the building is engineered to zero thermal loss allowing the pipework system act as storage in a unique design strategy.

The road to creating this low energy hotel began with rigorous testing on site which was boosted by the discovery of a massive energy reserve in the form of an underground river.

This discovery was inspirational in determining the mechanical design for the thermal energy system required for cooling and heating the building capable of using natural energy reserve.

The test well drilled to eighty meters deep at the rear of the hotel provides energy at 11°c for passive cooling the south side and having passed through the network rises to 16°c returning with enough energy to heat the north side without burning fuel.

The plant room, which was excavated under the basement car park, is an energy exchange system consisting mostly of pumps trained to follow performance routines.

Electricity to power these pumps and building is produced on site in a gas turbine to eliminate massive energy losses on electricity from the network.

Cooling the turbine produces the hot water for the hotel which is stored locally on each floor for instant use.

When the process of heating and cooling begins the system simply swaps energy from areas where there is too much to areas that require heat through an energy management system designed specially to eliminate wasting energy without compromising on comfort.

This means there are no emissions or harmful pollution created on site, only a small amount of energy is required to pump natural energy that already exists and the standby system is only being used during servicing.

The Iveagh Garden hotel electrical design minimizes electrical power consumption on all equipment that requires energy, lighting systems inside and outside were designed using LED low power lighting to enhance the desired result.

The entire building envelope has been sealed and insulated and existing glazing replaced to modern conformity with ventilation continuously monitored to insure clean fresh air for comfort living and energy exchange to prevent waste.

Water services were redesigned so that waste water operates gravity with no pumping energy required and lift systems replaced with low energy operating systems to all floors.

Enjoy a stay in the Iveagh Garden Hotel, realising every effort has been made to insure your stay is a positive effect on climate change, helping reduce global warming despite the comfort experience provided.

Management selected Ochsner Engineering as a key player in design alongside GNCE and Eurotech also delivered the renewable energy systems having previously teamed up with the Mc Gill family to apply renewable solutions in their Harcourt Hotel building.

Considerations & Benefits

  • Fossil fuel fired systems were removed to clear the way for natural powered sustainable systems engineered to EXEED.
  • An underground river flows fifty meters below the hotel and delivering endless energy for cooling & heating systems at zero carbon to combat Climate Change.
  • An underground natural energy distribution hub uses electricity produced on site in a gas turbine to run the pumps with zero grid losses on power and thermal energy.
  • The micro generation gas turbine cooling system produces the hot water for the hotel, stored separately on each floor close to ensuites and bathrooms avoiding secondary losses.
  • Waste water is engineered to operate gravity with no pumping energy required for discharge.
  • Heating and cooling systems swap energy between areas requiring higher or lower temperatures without burning anything, giving efficiency a whole new meaning.
  • The heating and cooling piping network throughout the building is engineered at zero heat loss to become a storage system that moves energy around similar to the Luas network.
  • A bespoke smart control system modulates pumps, switches valves and directs energies through the network with  precise timing to match energy exchanges on several fronts in an instant.
  • Power generation automatically tracks thermal and electrical energy requirements to deliver base loads off grid saving 50% on line losses and thermal losses simultaneously.
  • Heat recovery systems for ventilation regenerate fresh air by retaining the energy and enhancing the air quality through smart filtering.
  • Lift systems throughout the building use minimum energy to climb floors, employing counter balance systems to assist motion with swift smooth action and minimized carbon.
  • Catering kitchens renowned for wasting energy recycle the waste to heat fresh air flowing into the building for healthy living.
  • The hot water system is engineered to deliver fast hot water to showers and basins without the traditional secondary circulation systems saving 5,000litres and 260kw per day.
  • The lighting system uses LED low power lighting throughout the hotel inside and outside, standard bulbs that waste power are replaced and smart control illuminates areas being used to desired lux levels incorporating daylight for maximum comfort and minimum power consumption.
  • The Ivy Gardens is a natural co-existence where business and pleasure respect the power of nature on a daily basis to appreciate the revolutionary effect of renewable energy. The days of burning a flame at 1000°c to heat water to 65°c is gone for good, the management and staff of the Ivy Gardens are proud guardians of a precious planet.