A view into the workings of GPA

Basic Building Retrofit for Energy Conservation

This information comes from EI, the Education project by IEE – Intelligent Energy Europe, sponsored by IEEA, the Intelligent Energy Europe Agency. Lots of ‘E’s and ‘I’s as well as an ‘A’, but more importantly, lots of good information about energy retrofits of European housing developments. Their case studies focus on the run-of-the-mill social housing spread throughout the EU. …not very exciting to look at, but good for understanding the possibilities for changing modern energy hogs into teetoteling apartment blocks. They have studied renovations of social housing – varying from recently built housing blocks to those of the 50’s and 60’s. Like on many of our projects, the designers of these renovations were confronted with issues of tight budgets, weird funding sources, occupied rehabs and varying social situations.
Note that in most Europe, the residents of social housing generally pay for their own heat and water. So, their lives can be tremendously improved by renovations that reduce their energy demands.

I find it most interesting that the authors note that the individual heat recovery ventilation systems work well and improved indoor air climate. We have been looking for effective ways of introducing fresh air to our housing developments. However, we have been told by engineers that these systems are not cost effective to install in the Bay Area because of our benign climate. Since we know that the air quality in our residential buildings is not optimal – we tend to deal with stale or humid air in apartments by having a scavenger fan running 24/7 – basically throwing away the heat and sucking in air from wherever – the street, the corridor, who knows? These case studies provide a model for introducing passive heat recovery ventilation systems in apartment buildings in order to take the machinery costs out of the equation (see BedZED passive enthalpy heat recovery systems: http://www.zedfactory.com/pdf%20downloads/Load%20Reduction.pdf )
Anyway, here are EI’s recommendations & lessons learned (with my comments):

Main refurbishment measures – grouped in order of priority for achieving best performance. If you were able to do the first and second in each group, you’d have a high achiever.

• High envelope performance
- Insulation of façades [ preferably outside the existing façades ]
- Insulation of the roof [ the greatest percentage of heat loss is through the roof – heat rises ]
- Insulation of the top ceiling [ same thing – heat rises ]
- Insulation of the ground floor [ if you have a basement ]
- Double glazed windows with PVC frames [ maybe not PVC, but thermally broken ]
- Renovation of the balconies [ I think they mean balcony doors ]
- Renovation of the entrances [ replacing doors ]
• Improvement of the heating systems
- Insulation of distribution pipes [ helps prevent unintended heating or cooling as well as condensation ]
- Management and control system [ always a good thing, so long as it works well and is set right ]
- Installation of heat meters [ information can be half the battle – if people know that they are sucking heat, they tend to be more careful ]
- Installation of heat valves [ hopefully better than the valves we have on our radiators here in Cambridge – not effective at all – either on or off, although they have ‘0’ thru ‘7’ ]
- New energy-efficient boilers [ we can talk about condensing boilers later – a better alternative is biomass boiler, although I haven’t been able to find one in Califorinia – I have a feeling that they are banned due to air quality rules, although some East Coast biomass boilers are EPA approved in terms of air quality and seem to have very high efficiencies...more research warranted ]
• Installations
- Mechanical ventilation with heat recovery [ especially important in climates where heating loads predominate ]
• Renewable energy sources
- Solar thermal collectors [ more efficient than PV at converting sunlight to usable energy – by a factor of 10 or so ]
- PV-systems [ good for offsetting electrical use after all conservation measures have been done ]

Lessons learned and conclusions from the best practice examples.

Each of the more than 60 collected best practice examples includes a paragraph dealing with lessons learned and a paragraph dealing with conclusions on the specified renovation project. It is not surprising that these lessons learned and conclusions are often very similar, although, of course, most projects have their own special conclusions. The following points display some common lessons learned.

• It is worthwhile to involve and inform the occupants well and to listen to their wishes and proposals and, where possible, to fulfil some of them.
• It is very important to involve all occupants in the process of refurbishment.
• The energy saving potential is very high but is dependant also on the user behaviour.
• The individual heat recovery ventilation system has performed well and contributed to a much improved indoor air climate.
• The improvements of the apartment buildings increase their quality and the living comfort.
• The installation of solar thermal plants for the production of domestic hot water is a good solution.
• The total living costs after the renovation are in most cases much lower than before renovation.

More info at: http://ei-education.aarch.dk