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Archive for February 2015

Solar India

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India has been front and centre in solar energy news lately. What has captured everyone’s imagination is its intention to build the world’s largest photovoltaic array, a 750 MW plant in Madhya Pradesh to be completed in 2016.

Just as significant is India’s stated goal of installing 170 gigawatts of solar power by 2022, a short seven years away. Like China, India is aggressively moving towards renewable energy and away from polluting coal. Thirteen of the world’s cities with the worst air pollution are in India, with the capital, New Delhi, as the absolute worst.

The environmental and climate implications of this initiative are huge welcome news, clearly, but less obvious may be the implications for business. The State Bank of India, the country’s largest bank, has recently pledged a record $12.5 billion for renewable energy funding – a very welcome news as availability of land and capital have been identified as an issue for the development of solar energy.

Conversely, this is bad news for the business-as-usual coal industry; the push for renewables is further eroding the industry’s confidence in future investments. India’s domestic coal industry is riddled with corruption and inefficiencies, but the country has also pledged to cancel imports of coal (mostly from Australia) in the coming years (see here and here).

A solar array over a canal

A solar array over a canal

This large scale initiative is also supported by the US and by Germany, among others. India is also the first country to build solar arrays atop irrigation canals; this saves land, shades the canals and reduces evaporation, and the cooler humid conditions increase the efficiency of the panels (overly hot panels do not produce as much power as cooler ones). India has also built the world’s largest freshwater floating array (a 50 MW plant in Kerala); and Darnai, in Bihar state, became the first village entirely powered by solar energy.

Across the border, Bangladesh is also making strides, announcing its intention of becoming the world’s “first solar nation”. Already, fifteen million households are powered by solar electricty in the country. Pakistan, by contrast, is struggling, especially as chronic drought is reducing its hydro-power. Nonetheless, the country has a program to power irrigation pumps and reverse-osmosis desalination plants using solar cells. A 100 MW solar plant in Punjab has also been announced, which should be welcome news and hopefully enable Pakistan to eventually build a solar energy program at a scale similar to its Eastern neighbours.

Solar energy is reliable, stable, and cheap to run; in tropical countries, it contributes to job development, stability, and wealth creation.  So these are very welcome news for the three countries.

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Written by enviropaul

February 21, 2015 at 5:06 pm

Three new water books (3: Sedlak)

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indexThe three water books the KPU library recently acquired make a nice complement. If Everard’s is focussed on social fairness of water projects, and Tvedt’s marvels at how water projects have transformed our world, the third of the lot, by David Sedlak, takes a historical approach.

Sedlak, a professor of water resources at Berkeley, wrote his 2014 Water 4.0 by drawing on his experience with students constantly asking “why” type questions – and his realization that the answers are all grounded in history give the book a strong and compelling narrative.

Sedlak’s story focusses strongly on wastewater, surprisingly for a book that tackles water resources and drought problems. But Sedlak is convinced that water recycling holds the key to the future, hence the title Water 4.0, where the first three steps make up the bulk of the historical narrative.

Some of the historical topics have a contemporary ring, for instance, when one Frontinus, a water commissioner in first century Rome, complains that illegal sewer connections are a constant headache in his job; when Vitruvius is already aware of the dangers of using lead pipes; or when emperor Vespasian allegedly coins the saying “money doesn’t stink” when describing water collection.

At the same time, though, the enormous distance that separates us from these folks is clear. When Vespasian was talking about the smell of money, he was referring to the lucrative business of collecting urine to treat and clean wool. Or consider this anecdote from Japan in the shogun era:

Human wastes were separated prior to recycling. Fecal matter was the more valuable commodity, because solids are easier to transport. In the first stage of the recycling process, landlords sold the feces in their tenants’ cesspools to merchants who were members of a guild that had secured the right to collect the wastes from that part of the city. The wastes were so valuable that the rent of an apartment would increase if the number of people living in the house, and hence the amount of solid waste produced, decreased.

Imagine that: human waste is so precious that the more is produced, the less the rent. Wish we valued our own waste half as much!

In Sedlak’s scheme, the second phase in water management evolution was piping: aquifers and sewers, while the third phase was disinfection. A large part of the book deals with our various attempts to make water and wastewater safe, highlighting the differences between Europe and North America (as in, between chlorine and ozone, with a very thorough discussion of their various implications for health: cancer-causing chlorination by-products such as haloacetic acids, trihalomethanes, NDMA, or even increased levels of lead, versus the bromates formed by ozonation; and a mention that European cities, which sprawl less than their US counterparts, invest more in the maintenance and safety of their water systems, so need less costly disinfection).

Sedlak goes on to discuss wastewater pollution issues such as combined sewers overflows (noting, for instance, that Boston now having good wastewater treatment plants, half of the pollution in the harbour is due to CSOs), pharmaceuticals and other exotics in sewage (the best indicator of the amount of treated sewage in rivers is the concentration of artificial sweeteners), or that water and wastewater treatment in the US consume a whopping 4% of all the power produced in the country.

All of which leads Sedlak to advocate for what he terms Water 4.0: the closing of the water circle with conservation and recycling. Dipping a toe in the politics of water as right v water as commodity, the author notes with interest the progressive household water taxes of Seattle, which triple for any amount over the (still generous) 450 gallons/day. He also mentions the vacuum-flush systems that save water while allowing for energy recovery (a system being built in the Jenfelder Au development in Hamburg, for instance). Unfortunately, most of his material consists of drawing lessons from failed initiatives; for instance, he recounts how after Jay Leno quipped that Miller beer would need to change its “beech-wood aged” to “porcelain aged”, the (admittedly poorly named) Toilet-to-Tap Los Angeles program that would have recharged groundwater with treated sewage was dead on arrival.

If one is merely looking for a description of our current water issues, this book is competent, but not outstanding. However, using the past to shine a spotlight on our current issues and perceptions makes the book outstanding. For instance, consider this anecdote recounted early in the book:

In 1950, after suffering from a cholera outbreak attributed to pigs being fed on the town’s trash, local officials in Jasper, Indiana, passed a law requiring residents to install in their kitchen sinks the device that came to be known as the garbage disposal…The savings associated with the elimination of garbage pickups allowed the city to invest in a larger sewage treatment plant to handle the additional load of reduced organic compounds.

Using the sewers to dispose of garbage isnow  a complete no-no, and not only because much of our modern garbage is comprised of plastics; using garburators to dispose of food wastes is actively discouraged and even banned in most municipalities. This is because of the extra load that food waste would impose on wastewater treatment plants. But what if we used our waste to generate energy, using vacuum systems? This approach would actually benefit from using garburators (more energy would be available) while helping with garbage disposal issues. This is not an approach discussed by Sedlak, but it resonates for me (I’m a big fan of vacuum systems). Likewise, readers are bound to develop similar insights from the historical breadth and context used by the author to illustrate his material. If only for that, this book is a must anyone interested in water resources.

Sedlak, David 2014. Water 4.0: The past, present, and future of the world’s most vital resource. New Haven: Yale University Press

Written by enviropaul

February 15, 2015 at 12:15 pm

Three new water books (2: Tvedt)

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waterThe second book that caught my eye in the new acquisitions at Kwantlen is called A Journey in the Future of Water, by Norwegian water expert Terje Tvedt. If Everard’s book is focussed on big dams, Tvedt’s is broader in scope and more of a travelogue than an essay; it wanders through some of the more interesting spots that illustrate global water resources management.

For instance, Tvedt takes us to Brazil, where the world’s largest aquifer, the Guarani reservoir that partially lies under the Pantanal wetlands, covers an area of nearly two million square kilometers and holds 37,000 cubic kilometers worth of fresh water. Should this immense resource be developed, especially given the dire drought currently gripping Brazil? What would this mean for the Pantanal, the largest wetland wilderness in the world?

Tvedt also describes the Egypt’s Toshka project, a huge irrigation scheme to bring Lake Nasser water to a valley 300 kilometers away in the Sahara, and create from scratch a new irrigated farming community of over 2300 square kilometers. The author, a Nile watershed specialist, also describes the various Nile dams upstream of Egypt. There is this idea that Egypt would go to war to prevent upstream nations from “stealing” its waters, but this is belied by the fact that there are several large dams already built. The largest is Sudan’s Merowe dam near the near 4th cataract; a 1250 MW, 9km long, and 67 meters high dam completed in 2009, it’s 174 km long reservoir displaced 60,000 people. Ethiopia has also already harnessed the Blue Nile with the smaller Tis Abay and Tezeke Gorge Dams. Curiously, there is no mention of the proposed Millennium Dam, a giant project rated to 5250 MW; this project, expected to be complete by 2017, is the one that former Egyptian President Morsi threatened Ethiopia with war if the project was completed.

Tvedt also describes the potential for dams in Nepal; hydroelectricity could realistically generate 42000 MW, and the reservoir potential is such that the water flowing down to India could be increased four-fold during the dry season, potentially saving the health of the Ganges. As with the Nile, though, there is a curious absence of critical appraisal – would that be good? damaging? sustainable? The reader is left a bit hungry for comment. But in one way, this may be a strength of the book; instead of passing judgment, the author merely describes, sometimes with what may be a bit of unstated humour. For instance, one chapter describes how Greenlanders welcome for climate change: they plan to capture glacier melt in hydroelectric dams, and either export electricity to Europe or invite aluminum smelters (the first such dam has already been built at Tasiilaq).

But for all that, the breadth of the topic is spectacular enough that a documentary series has been adapted from the book; trailers can be seen here and here.

Tvedt, Terje 2014. A journey in the future of water. London: Tauris.

Written by enviropaul

February 15, 2015 at 11:57 am

Three new water books (1: Everard)

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One of the things that my employer, Kwantlen Polytechnic University, does well is stock up on good books in its library. Here are three recent acquisitions on water (and, no, it’s not me who ordered them; these three were pleasant surprises on the “new book” display).

everardThe first discussed here, Mark Everard’s The Hydro-politics of dams (2013) is particularly timely given the current controversy over Site C. The book is not a simple polemic pro or against big dams; rather, it examines closely how the impacts and the benefits are distributed – in particular, how the populations flooded by reservoirs fare. Nonetheless, there are ample facts and tidbits of info to feed into any large dam debate.

The Aswan Dam is discussed in depth, of course, as it is one of the projects that has seen the most thorough study. But until reading Everard’s book I never realized that the evaporation from Lake Nasser, the reservoir behind the dam, is equivalent to the total amount of water consumed in the UK every year; nor that the manufacture of fertilizers is one of the largest user of electricity produced by the dam. This is ironic because the dam holds up the silt that used to fertilize the delta each year at the flood; Egypt is also one of the largest importer of bricks, for the same reason.

In BC we know salmon, but there are other migrating fish everywhere in the world, and Everard does mention them. For instance, he describes how a stock of Hilsa, an important food fish in India, was completely destroyed by the completion in 1943 of the Mettur Dam on the Cauvery River – with scant thought to the compensation of fishermen.

Dams can also create oxygen-depleted, dead zones at the bottom of reservoirs, and these can have important implications, in particular when assessing the climate impacts of dams. In particular, these conditions promote methane release from decaying vegetation, to the extent that India’s large reservoirs account for 19% of India’s global warming impacts (India’s dams release 28% of all the methane produced by dams world-wide; Brazil is next at 18%).

A large section of the book is devoted to fairness and dispute resolution principles. For instance, Everard uses the example of Vittel, a bottled water company. Vittel gets all its water from a spring in the Vosges area of France, a traditionally wild area. But with the development of industrial agriculture in the area, Vittel was concerned that contaminants risk reaching the spring. The traditional avenues (e.g., purchasing the land, or putting a legal restraint on farming activities) were not available. Vittel worked with the farmers, paying the to return to extensive (pasture) agriculture, to their mutual benefit. Ditto for Perrier where the company paid to preserve the forests that protect the source.

Everard describes how earlier rulings that evicted and denied Kalahari Bushmen access to water in their ancestral lands were later (2011) quashed by Botswana’s appeal court, saying “The key lesson here is that top-down water management solutions that ignore stakeholder groups can result in infringement of human rights that may require subsequent restitution.”

The author uses this particular case to highlight the need to follow the seven strategic principles set up by the World Commission on Dams: gaining public acceptance; comprehensive options assessment; addressing existing dams; sustaining rivers and livelihood; recognizing entitlements, sharing benefits; ensuring compliance; sharing rivers for peace, development and security.

When I read those, I can only wonder at the current situation with the Site C dam proposal on the Peace River. Subsequent restitution is certainly a risk in this particular case, given the number of court actions already started, including some from Treaty Eight First Nations. In fact, looking at the WCD seven principles, I find several sadly neglected. The project is highly controversial and has failed to gain public acceptance, and not only from the folks directly affected. Comprehensive options assessments (in this case, considering alternative energy sources such as wind and geothermal) have not been done. The power production potential of existing dams (the Columbia river ones) has been dismissed. The livelihood aspects of the Peace River Valley and its potential for replacing California as a source of produce in a warming world has been paid lip service at best, despite numerous submissions to the commission. Finally, the “sharing of benefits” strategy remains rather nebulous.

In a way, Site C is a sort of anti-Aswan. The Egyptians use their dam to maximize food production, including using most of the power produced to make fertilizers. In BC, we would use the dam to produce electricity for export and neglect food production. I’m not sure this is a wise strategy for the long term.

Everard, Mark 2013. The hydro-politics of dams: engineering or ecosystems? London: Zed books

Written by enviropaul

February 15, 2015 at 11:31 am

Ordinary, efficient buildings

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A typical appartment block in Hamburg, retrofitted to high energy standards

A typical appartment block in Hamburg, retrofitted to high energy standards

Germany is rightly famous for its wind and solar energy, but there’s an aspect of energy policy that is easily overlooked: energy conservation in buildings.

Dinah's old home, the brick building behind her.

Dinah’s old home, the brick building behind her.

While in Hamburg Dinah and I walked to the building where she grew up, a rather ordinary brick appartment block. Little seems to have changed; but the building is now far more energy efficient (and comfortable) than originally. First to go was the dirty and polluting coal furnace. Then came the more recent renovations: insulation, windows, balconies, and a more efficient system.

This building and its renovations is typical. The country has a large stock of old houses, appartment buildings, and commercial buildings that consume about 40% of the country’s energy, mostly for heating. Even if they have little historic value, it is neither realistic nor desirable to have them replaced by newer, energy efficient buildings. Instead, these old buildings – mostly post-war ones – are progressively being renovated into energy efficient ones.

Named EnEV, the initiative started in 2002 calls for energy audits triggered by major renovations, and requires energy efficiency updates such that no more than 70 kW-hr per square meter is required for heating and hot water. The EnEV intiative has a very ambitious target of renovating 3% of the building stock every year; this would translate into halving the energy consumption of the building sector.

A detail of the building, revealing the added insulation

A detail of the building, showing the added insulation; the older brick is below

The approach to insulating, in particular, is quite unique: where in Canada we would usually add insulation to the inside of a building, Germans more often will insulate the outside. Panels of rigid, light insulation with a brick facing called ETICS (External Thrmal Insulation Composite systems) are glued to an existing outside wall surface, a relatively quick operation that minimizes disruptions for the building’s occupants. These systems have now been shown to be very long lasting and have a low footprint even when considering the full life cycle which includes such factors as the energy embedded in their manufacture. In effect, a whole new industry has been created, which is thriving and is now looking beyond Germany at a growing export market, as the clip below shows:

The building on the right has been renovated, the left one not.

The building on the right has been renovated, the left one not.

These renovations don’t come cheap, of course; some homeowners are looking at a 20 year pay-off period, or even longer. “I’m doing this so that I won’t have to pay much for heat after I’m retired”, says one, “and I expect the kids will benefit once they inherit the house”. This sort of long-term planning is unheard-of in North America where people are quite mobile and energy improvements rarely affect the value of a home. In Germany, the law mandates stating what is the enrgy performance of any home or appartment for sale, in terms of energy units and energy costs at the current energy prices. There has been grumblings among tenants associations, though, who fear that renovations will make rents unaffordable. Rents are regulated and landlords can only increase the rent by no more than 11 percent of the costs; nonetheless, such increases can be hard to bear for people on fixed or small incomes.

But for all the growing pains of this initiative, kudos to Germany for being pioneers in this approach. They are solving problems that we haven’t even started considering in Canada.

Written by enviropaul

February 7, 2015 at 8:58 pm

Riding my bike down history lane…

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IMG_3796I have developed a strange habit when I go on a bike ride around the city: I look at street addresses, and try to match them with some historical event or period.

Let me explain: I love cycling, I’m slow, I look at the scenery, the fresh air makes my brain work better; that’s when I get creative or nerdy ideas. I live near Commercial Drive in Vancouver, and the street addresses have four numbers, just like dates. This gives me a handy measuring stick for history: past civilizations, climate events, pollution episodes, what have you. History buffs, join me for the ride.

I start biking west, and just before getting to Semlin I run into the present year, a little house numbered 2015. Across Semlin, before Victoria, half-way down the block is house number 1956 – the year of my birth.

Wow – the dates that span my life cover less than a block. But what a period for the Earth: plastics, electronics, and pesticides became ubiquitous. The Anthropocene coincides with my own life span, so to speak, over a single half block.

The next houses down witness the worst episodes of air pollution in the western world, the Donora and London killer smogs, 1948 and 1952. And just past that is the beginning of motorized transport: Ford’s Model T, at 1908, and the Wright brother’s first flight, across the street at 1903. Toss in a couple of world wars in between.

Barely across Victoria, I notice a house with twin addresses: 1812, the year of the pointless war, and 1816, the “year without a summer”: global cooling caused by the Tambora volcano adds famine to the misery of war. This is also the block that sees the birth of steam engines, coal power, anddickensian tenements. Glad to see them come and go over a short block.

Across the street, 1799: Napoleon is fighting in Egypt, encourages his troops with the speech “soldiers, from these pyramids forty centuries looking IMG_3800down on you”. Hmm, I wonder how far down the street that is – Kitsilano, maybe?

Two blocks down, a 1618 address: the start of the thirty years war, where a third of the population of what is now Germany, the Czech Republic, Austria, and the Netherlands perish. And it’s cold; we’re in the middle of the Little Ice Age, and witches are blamed for crop failures.

At the corner of Woodland: 1492, Columbus sails the ocean blue. The Columbian exchange brought Old World diseases to the Americas, wiping out most of the population. Nature takes over former villages and farms; some people speculate that all this carbon sequestration contributed to making the Little Ice Age colder.

I see a house at 1066 before crossing Windsor: the Normans conquer England, defeat the Saxons at Hastings. Two blocks down, Charlemagne is crowned emperor as I cross Prince Albert (at 800). This area corresponds to the medieval dark ages; it’s cold again, agriculture gets more difficult as I ride up the block; ice forms on the Nile at 829, the Rhine is frozen solid a few blocks up, at 451, allowing Attila to invade and destroy what’s left of the Roman Empire. Maybe it’s because there was a large eruption down the block at 535, but regardless it’s really cold again throughout the whole area. (As I cross St-George, it seems fitting to think this is where the legendary saint slayed his dragon, around 500.)

Baby Jesus is born across Quebec street. As I leave the common era, numbers increase again. Caesar breathes his last at 44. I’m now 22 blocks from where I started.

Around Cambie the great oak forests of Europe are pretty much gone, felled by slash-and-burn agriculture; the Celts are spreading from Germany in all directions. Rome is a little village, but there’s a bunch of smart Greeks debating: Plato and Aristotle, Euclid and the vegetarian Pythagoras. Across the street – I don’t have the exact address – Buddha is preaching in Northern India, Confucius in China.

Near VGH, around 850, there is yet another major cooling in Europe. The whole area (the four blocks from 800 to 1200) are the other, older Greek Dark Ages; the Bronze Age comes to an end, because of climate change and drought. I cross Oak as King David captures Jerusalem and creates the Kingdom of Israel, at 1010. A block down, the Greeks lay siege to Troy, at 1184 just before Alder street.

Remember Napoleon’s speech at the pyramids? Before crossing Granville, Pharaoh Thutmosis IV sleeps in the sands near the pyramids. In a dream, he hears the sphinx ask: “remove the sand that covers me, restore my former glory, and I’ll make you a great Pharaoh”. Thutmosis obliges, goes on to win a major battle (against who? I forget). But for Thutmosis, the sphinx is already an ancient artefact.

In fact, I’ll have to ride up another eleven blocks, past Larch in Kits, in the 2500 block, to see the sphinx as it is being carved out, still the largest monolithic sculpture in the world; and the Great Pyramid of Kheops is built on the same block, number 2560. Before getting there, though, I ride through the blocks 1900 to 2200, around Arbutus; these witness a terrible dry period, when the Nile won’t flood, and famine destroys the Old Kingdom of Egypt. And yes, it’s been about forty blocks since Napoleon’s pyramid speech.

Past Balaclava (the 3100 block), Ötzi the iceman dies in the Alps from an arrow wound; he’ll be found only in 1991 by a couple of hikers, climate change having freed him from the ice where he’d been laying that entire time.

Crossing Alma at the 3700 gets me into Point Grey. Quite a different landscape: we’re leaving history. From that point onwards, there is no longer any writing to guide us; the first civilization, Sumeria, invents cuneiform writing somewhere near Dunbar. But the climate is much more amiable; the Sahara is just beginning to dry up. The hippos and giraffes won’t survive the change, but people are leaving the area for the reliable waters of the Nile, creating the future Egypt.

Another ten blocks up the hill I cross Blanca; what happened in the millennium between 4700 and 3700 BC? People came and went, leaving few traces. But by 5500 (at about the University Club), the seas have risen enough for the Mediterranean to connect with the Euxine Lake. This floods a huge expanse of land and creates the Black Sea. Scholars speculate that the memory of the flood is preserved in Noah’s Ark’s story. These flood refugees speak an early form of Indo-European, and as they disperse they become the ancestors of the future speakers of Iranian, Russian, English and other related languages.

By 6200 I’m at UBC, and I’ve run out of road. People have started farming in Europe, in the Balkans. We don’t really know who they are, but they are not ice age folks; these folks wouldn’t be seen for another 50 blocks, if there were such a thing – it’s as far again as my ride so far.

I imagine continuing on a course due west; at that scale, by the time I get to Port Alberni, we’re in 60,725 BCE, in the thick of the ice age. Modern humans (Homo Sapiens) have just moved out of Africa, spreading to the Middle East; the more robust Neanderthals live in Europe, or in that part of Europe that’s free of ice, with woolly mammoths. To get to the next interglacial, I’d have to get past Tofino.

By the time I’m somewhere north of Beijing, we are four and a half million years into the past; proto-humans are emerging. Lucy, our common ancestor, is only 3.2 million years old, and her birth corresponds roughly to the beginning of the Ice Ages (the quaternary epoch), somewhere mid-Pacific.

But even if I could continue on that course, I’d still be along way from seeing dinosaurs; it would be like ten times the distance between Vancouver and Beijing. Or consider the distance that separates the Earth from the Moon (384,400 km): that would put me in the Triassic era, the dawn of the Mesozoic, the age of the dinosaurs. And yet I would need to cover that distance twelve times over to witness the birth of the Earth.

And to think I already felt insignificant by the time I got to Point Grey…

On the way back I ride past the 2015 house again. How much further can I expect to go? Another house, maybe two or three with luck; but certainly not another block. That’s how short human life is. I look at a brand new house just finished, at 2086. I won’t make it there. Little Lukas, born in 2012, likely will walk through that door, but even he will be old by then.

IMG_3802On the 1600 block, people blame witches for crop losses and foul climate. Up the 2100 block, I hope we’ll be

smarter, and that for the sake of all the Lukas’s of the world, I hope that we can minimize how we’re changing the climate. A bit of a bumpy ride ahead, kid, but I know you’re tough.

Things can change quickly, though. In her wonderful book This Crazy Time, Tzeporah Berman quotes her grandma as saying, when Berman was a bit despondent: “you need to hold on to fact that the world can entirely change in your lifetime.” A lifetime? That’s one city block, and a lot can happen even over a short block. There’ll be surprises.

Lukas

Lukas

All right, enough day-dreaming. I live at east 2528, end of the ride. Hey, isn’t that when Star Trek’s Enterprise was launched?

 

 

(Note: the information on how past climate changes affected history is out of Brian Fagan’s 2004 The Long Summer: How Climate Changed Civilization, already a bit dated but eminently readable.)

Written by enviropaul

February 7, 2015 at 5:43 pm

The Jenfelder Au project in Hamburg

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Water and energy flows in Jenfelder Au..follow the flush

Water and energy flows in Jenfelder Au..follow the flush

Here’s something else that caught my eye when I was in Hamburg recently: the new Jenfelder Au development, which will derive some of its energy from wastewater.

A bit like the famous Vauban neighbourhood in Freiburg, Jenfelder Au is a re-development of an old army base, and like Vauban, solar energy and energy efficiency are prominent features. But the comparisons stop there: Jenfelder also embodies a brand-new approach to water management and energy generation. (Okay, okay, there is another difference: Jenfelder Au is still in development…just you wait, though!)

A view of part of the complex

A view of part of the complex

The project, a complex for 700 households laid out on over a 35 ha area (flat as much of Hamburg), has prominent water features: ponds, a basin, ditches with cattails and what have you. These are the core of the green infrastructure of the project: basically, when it rains, water is not rushed through storm drains, rather it is absorbed and released gradually by the vegetation and the basin, which can hold over 5000 m3 of runoff. Hamburg has embarked on an ambitious green infrastructure initiative (green roofs, new parks and infiltration areas, etc.) and Jenfelder Au should be a showcase for these.

But this isn’t what is really unique: rather, it’s the whole wastewater-energy nexus of the development. The way modern cities deal with waste (flushing them down with copious dilution water) means that there is little useful that can be done with them, since they are so diluted. Centralised wastewater treatments plants make biogas out of the sludge they remove, but that is usually barely enough to power the plants themselves, with little energy left-over. But if the waste weren’t so diluted, much more energy could be generated.

This is the approach that Jenfelder is following. All toilets are on a vacuum system, so that only about one litre of water is used per flush. This is expected to save about 7300 litres of fresh water per year per person (that’s a non-negligible 12,500 m3 per year). The vacuum system will convey the waste to an anaerobic digester. The digester will produce biogas that will generate both heat and electricity for the complex.

The overall plan, with the water features highlighted

The overall plan, with the water features highlighted

The biogas system (with combined heat and power) is expected to produce 100 kW of electrical power and 135 kW of thermal power, enough to supply 30% of the heating needs and 50% of the electricity. The rest of the energy will come from a commination of solar panels and a geo-exchange heat pump system.

All in all, the system is expected to reduce by 500 tonnes per year the amount of carbon dioxide that would have been emitted in a conventional residential development of that size.

Because the wastewater treatment system is decentralised, the proponents expect to develop systems that would recover nitrogen and phosphorus from the digested sludge, as well as preventing the release of micropollutants (such as pharmaceuticals) to the environment.

You have to give it to the Germans: they don’t do things half-way, and don’t mind trying new systems. They may well be rewarded for it: the Australian government has taken a keen interest in the water-saving and power system developed at Jenfelder Au, and may well purchase the rights to the technology.

More info can be found here, here, here, here, here, and here.  Or just look up anything related to the International Building Exhibit (IBA, in German) in Hamburg – you’ll be amazed what they’ve come up with.

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