The Emerald Project In Detail
Innovative Sustainable Design Strategies, Techniques and Materials at Emerald
Brian T O'Brien
The Emerald Project
2009/11
The Emerald Project is a project of two parts. The first part comprises 13 affordable houses, the second part 24 social housing dwellings (20 apartments and 4 houses). The two parts share community areas, energy and other services installations, and courtyard gardens. It’s located in Ballymun in Dublin and is designed by Solearth
Emerald will be Co2 neutral /negative the country’s first project to demonstrate the realisabilty of the new building regulations 2013 – with 2 years to spare. CLUID Housing Association are the lead client with Ballymun Regeneration Ltd (BRL) being funding partners and patrons of the project.
Emerald represents the most practical, most relevant energy, ecology and information innovations for housing in Ireland over the next generation.
The project has been in incubation for a number of years. The energy, ecology and information innovations represent a comprehensive and integrated suite of advances in; resource (energy, heat, water) demand reduction (efficiency), on site power and heat generation, and grid connection (with smart metering and load shifting), waste reduction (and on site treatment) water efficiency (and on site treatment), low embodied energy construction and transport advances, in the mass housing sector.
Objectives.
Zero CO2
The Emerald project aims to be the country’s first truly zero carbon (based only on on- site parameters) sustainable mass housing model solution.
Its goals are:
• To set a precedent for the creation of ultra low emission homes that are also healthy, affordable, and to demonstrate that zero CO2 homes do not impinge on the lifestyle and comfort of the occupants
• To test what the technical barriers to large-scale photovoltaic, solar thermal on site energy production, and grid connection (net metering) and group scale wastewater recovery and rainwater harvesting are.
• To quantify the technical risks to scaling up low embodied CO2 construction materials and renewable building service approaches, to a community scale.
• To explore the creation of buildings that are A-Rated under DEAP.
Measurability:
The project will include resource monitoring and metering systems that allow:
• The moment-to-moment resource use profile be displayed live.
• That period-by-period use resource profiles be recorded / analysed at any moment and over any period.
Verifiability:
A post occupancy evaluation study will be done at 1 and 3 years after commissioning and the results published.
The real time resource monitoring (and display) system will provide a set of records of resource usage (power, heat and water) and comparison with occupancy patterns and a profile of the resource demands and the sourcing of these i.e. CO2 intensive or renewable- to provide a net CO2 overview.
Selection Principles:
The design team have selected technological approaches, to address the above aspects, based on three principles that are intended to ensure that the outcome is a holistic and practically realisable scheme.
1. Selection of systems that do not unduly affect lifestyle/ rely on behavioural modifications.
2. Grouping of services for efficiency and control.
3. Integration of services into architectural and structural design.
Specific Innovations;
The project will try to address the most pressing building-related environmental challenges utilising a limited spectrum of carefully selected technological approaches. These will be optimised to work with a range of passive design features, themselves tuned to, and developed with, the future users. The proposed inclusions are integrated solutions that combine to create a replicable, workable, affordable, low or negligible emission project.
The project proposes the following model technologies in order to address the above challenges:
1. Co2 Free Heating / Comfort.
2. On Site Renewables
3. Power consumption efficiency
4. Passive ventilation heat recovery
5. Water recovery and efficiency
6. Smart electrics
7. Resource use feedback monitoring
8. Low embodied energy (healthful /natural ) materials)
9. Super Insulation
10. Innovation in heat delivery
11. Habitat and sustainable urban drainage
12. Transport Innovations
13. Monitoring and Evaluation
14. Food and Waste
15. Expertise building
16. Efficiency through design
17. Replicabilty
In more detail the innovations are;
1. Co2 Free Heating / Comfort.
Space heating at the project is fed from a large scale (100kwh) biomass boiler. Heat is distributed to all blocks via heat grid and back up heating si available via a (90kw) high efficiency gas boiler. All usage is monitored per apartment.
2. On Site Renewables
The scheme incorporates 332 sqm of (4.25kw peak) of building integrated photovoltaic panels.
and 130 sqm (ie130kwh peak of solar thermal evacuated tubes. These systems are semi grouped.
3. Power consumption efficiency
Discretionary (lifestyle) power consumption is cut down by provision of;
Cool larders; bespoke insulated cabinets integrated to the kitchen design which use heat exchange to maintain a cool temperature for storage of many items often stored in fridges unneccssarilly
Also clothes drying using sunlight is optimised by provision of conservatories and a community room designed like an atrium
4. Passive ventilation heat recovery.
Non mechanical heat recovery ventilation using Danish ventilation windows (vw) and bespoke roof top cowls
- The windows located according to the ventilation needs of different rooms have the following advanced characteristics; 300 watts /msq (of vw) per year energy benefit of glazing per year
- 70 % heat recovery without electricity (ie no fans)
- 3 cubic metres ventilation per hour per msq (of vw) area
5. Water recovery and efficiency.
The project has 3 water efficiency advances two supply side;
- Rainwater harvesting and re-use as ‘blue’ water in hot taps of kitchens and WHBs, hot and cold to baths and showers and cold to dishwashers,
- Grey water recovery and use as ‘green’ water in WCs and cold feed of washing machines. Pumping for this is done with PV) effectively replacing the power requirement for water pumps (which must be constantly available) with intermittently available solar power through raising the required water to roof top storage tanks.and demand side management through specification of low flow sanitaryware appliances etc
6. Smart electrics;
- Radial circuits for reduced EMFs.
- Grid connection and (net metering)
- Smart metering enabled (wiring to allow splitting into essential and not essential circuits)
7. Resource use feedback monitoring
- Live information readout in terms of current availability and usage of on-site generated versus imported heat, power, water and ventilation air at the apartment scaled
- Live, historic and comparitor readouts at the project scale resource usage within the visitor centre
- Back of house full monitoring BMS which monitors, records and reports data for above readouts
8. Low embodied energy (healthful /natural) materials.
Emerald is unique in placing he emphasis on achieving zero carbon / low energy homes (A1 to A2 DEAP rated) without relying on energy intensive, polluting and possibly toxic materials (ie foam, gas, styrene or polyisocyanurate Insulants) in its above ground elements. Clay, timber, wool, wood and lime based materials are used instead in the walls, roofs, partitions and skins of the building.
9. Super Insulation.
The building elements are designed to have ultra low heat loss (conductivity);
Walls and Roofs have U values at 0.12 W/msq
Air-tightness is a priority with detailing and specification designed to achieve a standard of
3 air changes / hour at 50 Pascal (Q value) maximum
10. Habitat and sustainable urban drainage.
The project incorporates green sedum surface habitats to all roof areas ie extensive green roofs. This offers habitat for insects and birds and combats heat island affect as well as settling urban dust. The majority of the courtyard is treated with porous surfaces and all water is collected (below the surface) for re-use. Both f these innovations fight flash flooding by providing rain storm attenuation.
11. Transport Innovations;
The project achieved planning permission for 2 electric cars and is equipped ot have charging facilities for them. Bicycles facilities are prioritised and the scheme is on the many main bus routes and the proposed Metro North.
12. Monitoring and Evaluation.
The BMS system to be installed in the scheme, in addition to running the background functions of plant and service installations, will monitor and display both instantaneous and historic figure for energy, water, heat and ventilation air usage. The figures can be recorded and used for later research and comparison.
In addition the project has a number of other low cost innovations that are not easily accountable under energy or C02 analysis but which nonetheless ensure the project contributes to all aspects of what we term full spectrum sustainability.
13. Food and Waste.
Food growing spaces are provided both communally (in the courtyard and the central conservatory / community space) and privately in residents own garden and terraces. Terraces and the main gardens have irrigation taps.
A high performance automatic composter is located in the waste and recycling room and the garden has a green waste composting (maturation) area.
14. Efficiency through design.
The project design creates inbuilt efficiencies and thus resource savings when viewed holistically and over the course of the life of the building
Grouping of systems; Grouping of heat, water and (partly) solar systems over the scale of 37 units provided major efficiencies and reduces losses.
Solar layouts; Despite having a non south facing site (the main building lines generated from the Ballymun masterplan run northwest to southeast instead of the more ideal orientation of east west). The design overcomes this by creating south facing (wedge shaped) conservatories to all blocks ( and pushed back terraces at roof level of Block A), to re-orientation part of each dwellings elevations to true south. Dwellings are only 2 spaces deep with living rooms are located to south and service rooms or bedroom to the north. All units bathrooms and kitchens have real windows for purge / summer ventilation (as well as the passive heat stack ventilation systems) and
Life Time Design
The residents changing requirements in terms of family size changes are designed in as follows. The scheme is constructed with 1, 2 and 3 bedroom units so that families can move between units over the course of their lifetimes. Block B houses are 2 storey 2 bedroom units and are designed to accommodate the addition of 1 bedroom to the roof as a third storey- making them the same as block D homes (ie 3 storey, 3 bedroom houses). These can in turn grow with the addition of a pre-designed room unto the terrace space to become 4 bedroom units. The 2 (2 bedroom and 3 bedroom) wheelchair friendly units (block C) provide further potential for resident to stay within their community as their situation may change.
As can be seen the project looks at both demand and supply side efficiencies, on site production of energy (and elimination of Co2) innovations and, crucially, addresses water resources and transport as well as energy and waste.
This will be the first time that such a level of progress has been reached in raising Ireland’s housing stock to best international standards, it will be the first time in the State that such a careful blend of advances have been integrated together, the first time that most of these innovations will have been used in a project of this size, and certainly the first time that most of these will have been used in social housing.