Here is an interesting image, the infrared image of Hong Kong Island promenade, the sum has been shining all day and the path is absorbing the sun’s energy, the walkway is warmer than its surroundings. At night, that stored energy keeps the area warm, warmer than the air temperature, a good example of the urban heat island effect.
Infra-red is accurate and very sensitive, the image even shows the edges of the manhole covers!
It is not too difficult to avoid this problem (remember white reflective roof post) choose a material with a high solar reflectance index (SRI) say 80 or above, that will reduce the energy absorbed.
We know there are insufficient resources to go around, right? Perhaps not. However, there are options, the idea of one planet living (http://www.oneplanetliving.com) gives guidance, like David Letterman’s feature, it provides a convenient top ten list, but how can we migrate from the status quo to a more sustainable future?
Green Building or clean technologies? What is the solution? Well in reality it is not that easy, I have seen Variable Frequency Drives (VFD) intended to provide fan speed control and save energy, locked at one speed, I have seen the building’s central chiller plant operated when one room demands cooling, I have seen room temperature sensors located above lighting fittings (lights are heaters) therefore the air conditioning system continuously calls for more cooling. etc.
So if I have learned one thing, it’s not the latest new idea or the wizbang technology itself that matters, what really matters is how we use the equipment and operate the facilities.
But before we all become operator angels, we will need to optimise and improve design, and not just buildings, but their context, we need more design not less, and we have to be prepared to pay for it. The challenges we face require scaled solutions, beyond a single building, and communities provide sufficient scale to enable working solutions (see also Every Community a Powerhouse).
And these solutions should be local. In my diagram above, waste can be managed AND reused. For example, water a separate stack would collect greywater for reuse primarily within the community, for example irrigation or process water for local industry.
Its more important than ever before that Eco-districts cover all aspects of our daily life including work! In the USA vast cities developed where work and home are very separate, with little public transportation, the urban sprawl created the un-walkable distance, increasing the demand for a private car, and in reality more than one car.
Creating distal residential areas in remote isolation is a recipe for disaster, we need closer communities, communities where certain resources can be shared or call them eco-districts, which are places we can work, play, and live.
We must optimise the use of resources, rainwater can be captured from several buildings are used communally for industrial use, irrigation, or your local energy generation. We have become accustomed to throwing things away, out of sight – out of mind, but there is no away, a far better solution is to handle all waste locally, and yes we should encourage more recycling, but we must be practical, and the local reminder (that there is no away) should be visible in your backyard, and it should be used locally whether for power generation, compost, or biogas (fuel for cooking) when possible locally.
We invest in expensive and energy-hungry air conditioning systems for offices that are typically used 9-7, then we repeat the investment and resource use, providing air conditioning for homes, with a little planning forethought, and load profile analysis, one AC system could serve both the office (during the day) and our homes (outside office hours), this natural synergy would save considerable cost and resource use.
The technology exists, but that is the easy part, we need solutions at scale, we need Government, stakeholders, communities to embrace change, and start managing and operating the entire planet.