Università IUAV di Venezia, Efficienza Energetica e Sostenibilità Magistrale Architettura e Innovazione Near Zero Energy Building: Same built example Fabio Peron Università IUAV - Venezia Zero Energy Building: the first self-sufficient house Self-sufficient Solar House Freiburg Germany Fraunhofer Institute Self-sufficient Solar House Freiburg Germany Fraunhofer Institute Regenerative fuel cell: PEM electrolysis unit (30 bar / 2 kwel) H2/O2 storage tanks PEM fuel cell No mech. compressor! BedZED, UK (2002) The Beddington Zero Energy Development (BedZED) project in Hackbridge, London was an attempt to create a zero energy community. Consisted of 99 super insulated dwellings of various sizes, workspaces and community facilities. Triple glazed windows. on site zero carbon generation provided by a prototype 120kWe wood waste fuelled combined heat and power (CHP) system with 777m 2 of photovoltaic panels designed to meet all of the energy demands of the residents along with providing the potential to power up to 40 electric vehicles at some future date.
Monitoring indicated: that space heating demand was 90% lower than the UK average electrical power consumption for appliances and lighting was 33% lower than average, however this was still higher than anticipated due to residents using back up electrical water heating The development did not achieve zero carbon operation, primarily due to the fact that the prototype biomass CHP system was unreliable and never operated effectively (it was shut down in 2005) The remaining PV system only offset around 20% of the total energy demands of the community with the remainder being drawn from external supplies Quartiere Bo01 a Malmö (Svezia) Minnesota Science Exhibition Building (USA) Minnesota Science Exhibition Building (USA)
Portland House, Australia (2009) Demonstration family dwelling in Portland Victoria with a super insulated and tightly sealed fabric, thermal mass and a cooling tower (promoting stack ventilation) for summer cooling All appliances in the dwelling were lowenergy Energy was provided by a 1.4 kw PV installation and 3 solar thermal panels augmented with an electric back up heater were used to meet the dwellings hot water demands A reversible heat pump met the dwelling s small space heating and cooling requirements. Monitoring over the period September 09 to June 10 indicated that the PV installation provided 93% of the dwelling s electrical energy consumption Note that this period did not cover all of the winter months and it is likely that the quantity of imported electricity will be slightly greater over the course of a full year. The developers have since indicated that the PV installation is due to be doubled in size to a capacity 2.8 kw. Given the current performance, this is likely to turn the building into a net electricity exporter. Wheat Ridge, Colorado (2005) The Habitat for Humanity home in Wheat Ridge, Colorado is a 119m 2 super insulated dwelling e.g. the building features low e solar glass with argon fill and a U value of 1.14W/m 2 K Renewable heat provided by a 9m 2 solar collector with a 760 l thermal store, backed up by a gasfired water heater Renewable electricity provided by a 4 kwp rooftop PV system The building also features a mechanical ventilation system with heat recovery. Monitoring indicated that during the period April 2005 to the end of March 2007, the PV system produced an excess of 1542 kwh Gas consumption for the water heater amounted to some 1670 kwh. The net site energy requirement for all fuels of the home was approximately 0.6 kwh/m2/year. Richardsville Elementary School
Richardsville Elementary School Lighthouse Zero Energy Home (UK) Masdar City (Abu Dhabi) Saint Louis Missouri Zero Carbon Office building prototype
Singapore Zero Energy Building Building and Construction Authority (BCA) Academy Zero Energy Office Building, Pearl River Tower, Tobacco Company Guandong China Westford Habitat Based on recently-built house Super-insulated enclosure Very airtight (1.5 ACH ) Best-in-class mechanical systems Energy Star appliances Compact fluorescent lighting No renewable energy added: not NZE (PVs or solar DHW) 1.5 Story Single Family Home with Conditioned Basement (2200 ft2 total) Malaysia Low Energy Building and Zero Energy Building
Westford Habitat Instantaneous Water Heater Fantech ERV Westford Habitat: parametric analysis 2 2 200 200 1 1 100 100 million Btu/year million (source Btu/year energy) (source energy) Enclosure improvements Mechanical improvements Appliance, lights 53% 0 0 Benchmark Benchmark Benchmark Benchmark As-built As-built As-built As-built base base base base Air Air Air Seal Air Seal Seal Seal R-46 R-46 R-46 R-46 Wall Wall Wall Wall R-66 Roof R-66 R-66 R-66 Roof Roof Roof R-26 R-26 R-26 Bsmt Bsmt Bsmt R-26 Bsmt Triple Triple Triple glazed glazed glazed Triple glazed 95% AFUE 95% 95% 95% AFUE AFUE AFUE 16 16 SEER SEER 16 16 SEER SEER HRV HRV HRV HRV DHW DHW 0.82 0.82 EF EF DHW DHW 0.82 0.82 EF EF CFLs CFLs CFLs CFLs ES ES Appliances Appliances ES ES Appliances Appliances Smart Smart Controls Controls Smart Smart Controls Controls ZEB examples: lessons From the evidence of the case studies achieving zero carbon operation is not straightforward! A building designed to be zero carbon does not necessarily perform as zero carbon Most fail to achieve this due to 1) underprediction of demands at the design stage 2) over prediction of energy yields from renewables or 3) poorly performing equipment in situ PV seems to be the ubiquitous option for electricity generation Most achieve significant reductions in thermal demand less success with curbing electrical and demands Heating Heating Cooling Cooling Hot Water Hot Water Lighting Lighting Other Other Reduction Reduction % Heating Cooling Hot Water Lighting Other Reduction % Heating Cooling Hot Water Lighting Other Reduction % % ZEB: design and construction process strategy
ZEB: simulation ZEB: simulation Aggregating the data from the simulation gives the following annual performance characteristics Base Case Dwelling Zero Carbon Dwelling Heating demand kwh 3083 372 Hot water heating demand kwh 2342 18 Electrical Demand kwh 5776 3240 Total Demand kwh 11201 5462 PV Output kwh 23 Solar Thermal Output kwh 1709 Biomass boiler Output kwh 1172 Total Production kwh 7904 ZEB: design and construction process strategy ZEB: simulation