Right idea wrong scale

waste to energy

Handling food waste is a global problem, but is all food waste equal?  There is waste from dining generated in homes, restaurants, and Dai Pai Dong’s, and there is food waste from markets, wet markets, and supermarkets, the latter being merely past its sell by date. HKSAR Government intends to create four food waste to energy plants, but no mention of their location and tragically RTHK’s report confirms our fears, about 3,000 tonnes are dumped into landfill every day! That is 1,095,000 tonnes per year.

community, eco-districts, waste to energy

However, collection, handling, shipping it across the territory, and bulk storage in central facilities is the worst possible solution in my view. To tackle local problems we need local education and local solutions, shipping it “way” will only perpetuate the most common reaction NIBMY.

Eco-District or community scale solutions demonstrate locally there is no distant landfill to handle the waste, you use it, you see it, you handle the waste. Therefore encouraging participation in the solutions, today’s over emphasis towards Green/Smart cities overlooks an important aspect, the human scale. The biggest challenge for eco-districts will be success, where the WTE (waste to energy) plant and equipment is designed for the worst case scenario, and the neighbours begin to understand that their waste creates a local waste problem, over time the total volume of waste will shrink, leaving oversized equipment in its wake. We need District, not City scale solutions.

One Planet Living

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 some guidance, like David Letterman 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 locked at a set speed, I have seen the entire central chiller plant operated when only room demands cooling, I have seen room temperature sensors located above lighting fittings (heaters) therefore the system continuously calls for more cooling. etc. So I have learned one thing, its not the latest new idea or the wizbang technology itself that matters, what really matters is how we use equipment or operate the facilities.


But before we all become angel operator, 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 is 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. It si 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 called 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 our 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.

A Thermal Bridge Too Far


The building structure, columns and floor slabs cant be seen with the naked eyes, but are clearly visible as purple colour in this infra-red image. the columns and floor slabs are cooler than the infill sections of the walls and the windows. The red/white hot spot is off the scale, it is caused by a electric sign, hotter than the building structure. Overall I think it nicely demonstrates that buildings which we perceive to be uniform in appearance actually have different paths for energy leakage, we call it thermal bridging.

Sustainability Primer


Here is a TED talk, it is an interesting primer for environment and sustainability issues (and I doubt the speaker Leyla Acaroglu will thank me for that). But I do wonder is sustainability finally heading towards the main stream?

There is no doubt that the analysis is incredibly complex, and the possibly the most significant factor, us, the end users, cant be easily modelled, or predicted, Just consider the factors for the paper vs plastic, how to account for the damage cause to ecosystems from the tonnes of plastic waste waste floating in the oceans, out of sight – out of mind. Look at http://projectkaisei.org which illustrates the vast cities of plastic that was dumped on to the ecosystem.

The Electric kettle is interesting too, since families here often boil the potable water before using it for drinking water, and that stems from water rationing in 70’s and 80’s coupled with the corroded steel pipes used for distribution prior to 1994, and the complete absence of maintenance for the central water storage tank, it is no wonder your parents had the boil the water. Assuming we 3,000,000 households boiling a standard 1.7 litre kettle, that’s 5,100,000 litres of water boiled (at least once) per day, the energy consumption alone is an huge environmental burden.

But don’t be fooled into thinking I am reminiscing about the past, my office is located in a pre- 1994 building, the water pipes have corroded, and water is usually brown in colour.

Serious About Energy

The SCMP (unlinkable) published an article on 7 Feb 2014 reporting the HKGBC as saying a few tweaks will save energy. Really, is it that simple? In reality it is not. Surely the time as come to get serious about energy consumption in Hong Kong buildings.

SCMP 7 feb 2014 (unlinkable)