This article looks into integrative design and sustainable buildings.
Last week’s article which you can access via the link below explored the most important idea in energy efficiency. Which we identified to be integrative design.
This week looks into how the idea behind integrative design can be applied to buildings. It is based on the Amory Lovins 2018 paper How big is the energy efficiency resource?
One of the first examples he gives, is the well-known 2010 retrofit of the Empire State Building. The integratively designed whole-building retrofit cut site energy use 38%, from 277 kWh m−2 yr−1 (slightly below the US office median of 293) to 173 kWh m−2 yr−1.
On this project, the majority of the efficiency gains were paid for by $17.4 million capital savings from making the cooling systems one-third smaller to match the reduced cooling load, rather than replacing them with larger new ones (plus bigger electrical risers).
Amory Lovins points towards the impressively efficient Rocky Mountain Institute Innovation Center in Basalt, Colorado that records an efficiency rating of 51 kWh m−2 yr−1 in a much colder climate. It manages to do this with no-boilers, no-chillers and provides more energy to the grid than it uses. net-positive.
Amory Lovins also points towards evidence from the IPCC which suggests that superefficient new and retrofitted buildings need not raise construction cost until energy savings reach at least∼80%–90% if then.
The paper also looks into Zimbabwe’s largest office and shopping complex, the 31 600m2 1996 Eastgate Centre in Harare, which uses biomimetic passive cooling and ventilation design (modelled on termite mounds) to save 90% of mechanical energy and deliver normal or better comfort at normal construction cost.
One of the key takeaways of Amory’s paper is that integrative design makes order-of magnitude building efficiency improvements inexpensive (or even cheaper than normal), mainly by eliminating or shrinking and simplifying HVAC equipment.
He explains that this enables total demand reductions of around 4–6×, not the usual <2×, thus expanding cost-effective energy savings by >2×.
Amory also points to how major building systems and functions often reveal hidden opportunities to do the right things in the right order and thus save even more energy at lower cost. He uses the example of LED lighting, which as you can see below is only the sixth priority in the steps recommended in the Illuminating Engineering Society’s Handbook of Fundamentals.
- Improve the visual quality of the task
- Improve the cavity reflectance and geometry of the space
- Improve lighting quality to cut veiling reflections and discomfort glare
- Optimize lighting quantity
- Harvest and distribute natural light; and then
- Raising source efficacy
- Optimize luminaires
- Improve controls, maintenance, and training.
Amory also points towards the American Society of Heating, Refrigeration, Handbook of Fundamentals, whose top advice below is widely ignored.
- Cool the people, not the building
- Exploit all comfort variables to expand the range of conditions in which people feel comfortable
- Minimize unwanted gains of heat and humidity into the space
- Passive cooling (ventilative, radiative, ground—or groundwater-coupling
- Active non-refrigerative cooling (evaporative, desiccant, absorption)
- Coolth storage and controls
Amory also points out that the capital savings from shrinking or eliminating HVAC equipment in new buildings can also be largely obtained in retrofits by timing deep retrofits to match routine major renovations, such as renewing HVAC systems or façades.
He points towards smart building examples that apply advanced glazings that insulate better, look clear, pass abundant daylight, but block unwanted heat transfer, and are spectrally ‘tuned’ to each direction.
What you need to know
This article looked into integrative design and sustainable buildings.
It is based on the Amory Lovins 2018 paper How big is the energy efficiency resource?
The key takeaway is that savings were achieved through integrative design, not by adding more widgets, but by leaving more out.
This week looked at buildings, subsequent articles will look at mobility and industry.
Thank you for reading,
By Barnaby Nash
Please share your thoughts in the comments section below, or reach out to me on social media. What do you think the most important idea in integrative design is?
Let’s stay connected