Green-minded architects and builders are familiar with the Forest Stewardship Council (FSC), which certifies timber as sustainable. It's attracted its fair share of criticism, as a quick look at the blog FSC Watch indicates (the blog even has a section devoted to certification in Ireland). Still, FSC certification is one of the few ways specifiers have of knowing how well a forest is managed when they're choosing timber.

Now another certification scheme, the Programme for the Endorsement of Forest Certification (PEFC), is getting up and running on these shores. In an email to Construct Ireland, PEFC Ireland 's William Merivale wrote:

There are two distinct areas of our work.  Firstly we are involved with drafting an Irish forest management certification standard which we expect to be ready for submission to PEFC International for endorsement by late summer/early autumn, and once endorsed both State and private forest owners will be able to apply to have their forests certified by PEFC.  (You may be aware that in the UK the Forestry Commission and a significant area of  private forest managed by Scottish Woodlands/Tilhill have recently opted for dual certification to both FSC and PEFC and we are confident this will happen here as well.)  Secondly we promote chain of custody certification to as wide a range of businesses involved in the manufacture/supply chain of wood-based products, and to their consumers.

Hopefully the arrival of PEFC will improve awareness of forest certification further - I've been surprised once or two recently, talking to people who work in various parts of the timber industry, at their lack of awareness of these certification schemes. Saying that, one architect I spoke to made the valid point that certification marks like FSC or PEFC discourage specifiers from doing detailed research on where timber comes from and deciding based on that - he argued they encourage laziness in timber selection, essentially. It's a reasonable point, but he also acknowledged - rightly - that the likes of FSC and PEFC are necessary for the many specifiers who want a green product but don't have the time or motivation to do serious research.

Most flat plates and some vacuum tube systems show efficiencies of around 80%, but when you look at the EN certificates for most popular Chinese vacuum flask systems, they are often in the mid 60s or less. Many people assume that this reflects poor quality Chinese manufacture, but in fact it is a quirk in how we measure “zero loss efficiency” which is at noon, and ignores the effect of the sun facing tubes at different angles at different times of the day. This factor is included in test results, described as transversal incidence angle modifier, or IAM.

The efficiency of a panel is usually given for noon when the sun is directly facing the panel. With a flat plate panel, efficiency falls off either side of noon, but with vacuum flasks, the efficiency actually increases. There are two reasons for this.

Firstly, the curved surface of a tube passively tracks the sun. Secondly, whereas at noon, the sun shines between tubes, as the sun moves towards 40 degrees off due south, there is increased reflection from tube to tube, dramatically increasing absorption.

The effect of this change in incidence angle modifier is measured as part of the test procedure for EN12975 certification. To show efficiency at any particular time of the day, the zero loss efficiency should be multiplied by the IAM.

The following chart shows a comparison between the IAM of a typical flat plate system and an Ecologics 58mm flask system at different angles as the sun moves from Noon to evening. A mirror image of this graph happens between sunrise and noon.
 
At its most extreme point, with the sun at an angle of 60 degrees, the output of a flat plate would be reduced by 10%, whereas the flask system’s efficiency is actually increased by 44%.

The difference between flasks and tubes
Chinese vacuum flasks are like a thermos flask with two layers of glass and a vacuum between these layers. There are many advantages to this:

• The vacuum element is a single piece of glass, whereas many other vacuum systems have a single layer of glass with a join between the copper heat pipe and the glass forming a seal to maintain the vacuum. With extreme temperatures, especially in stagnation, this seal can fail.
• Flasks are modular. When they lose their vacuum (typically expected after 15 - 20 years) only the flask itself need be replaced. Tubes require the replacement of tube, heat pipe and collector as a single unit.
• Replacement flasks are in common sizes of 47mm and 58mm diameter, produced in numerous plants in China, so you are not reliant on one supplier for spare parts. By comparison, most tube systems are not interchangeable. 
• Replacement flasks are typically about €5 each, whereas replacement tubes are considerably more expensive. 
• Chinese flask systems may be more sustainable than either tube or flat plates. Flat plate panels usually have a life expectancy of about 35 years after which the entire panel needs to be replaced with enormous disruption. An aluminium or stainless steel manifold on a vacuum tube system should last as long as the roof, with just a requirement to exchange flasks every fifteen to twenty years. This also dramatically reduces the embodied energy of the components required to maintain the solar water heating system over the lifetime of the house.
  

 
For these and other reasons, Chinese flasks have been widely adopted, and many – but not all – are of excellent quality and durability.

BER assessments
Modern houses with their improved energy efficiency could benefit more from vacuum systems because the central heating is operating for a shorter season, and vacuum systems have a longer operating season which complements this nicely.

A problem arises when you try to use the figures for vacuum flask systems in DEAP for BER assessments and Part L compliance. Commercial solar simulation software takes the IAM figures into account, but despite requests to SEAI going back almost two years, there is still no way to incorporate IAM in Deap.

You might think that you could simply take the ratio between the two average IAMs as a multiplier. The reality is more complicated because the multiplier should reflect the amount of time that the sun spends at each angle, and efficiency will also change as fluid temperature and ambient temperature changes throughout the day. You also get different effects depending on the roof pitch, orientation, and the amount of sunshine.

We ran identical panels through simulation software with each of the IAM curves shown in the graph, using various roof pitches and locations in Ireland. These showed a net increase in output of between 16 and 19% as a result of the altered IAM.

Not all vacuum flask systems have the same IAM curve, and it would be difficult to develop a formula that would reflect the effect. However, it would seem reasonable to allow BER assessors to increase the zero loss efficiency used in Deap provided they or the panel manufacturer can produce documentary evidence supporting this change for the conditions.

In the case of the example shown in the graph above, the multiplier would bring the zero loss efficiency from 66 to 78.4%. When you take into account the true efficiency, combined with the improved heat loss coefficient of vacuum systems, it becomes apparent that vacuum flask systems are extremely efficient at all times, often at a lower capital cost, and with lower long-term maintenance costs.

IAM for tubes with an enclosed flat plate
Lastly, it should be stated that this situation does not apply to vacuum tube systems which have a small flat plate inside a single glass tube. Their IAM more closely resembles that of a flat plate panel.

Quentin Gargan is a lecturer on the Fetac solar training in Cork Institute of Technology and is a founding director of Ecologics Solar Solutions. He has worked with both vacuum flask systems and Austrian flat plates, and would argue that commercially he has no axe to grind.

You may remember the Solar Decathlon, a US competition that challenged university teams to design the best solar-powered house. We previously profiled the competition in a lengthy photographic feature.

The sliding metal shutter shades of the Lumenhaus can be used to protect the house from glare and overheating, or pulled back to let sunlight in fully

For the first time this year a separate Solar Decathlon was held in Europe - Madrid specifically - and Virginia Tech's Lumenhaus (above), which also entered the US competition, emerged victorious. Green Building Advisor has more on the Lumenahus, and the official website has lots of information on all the houses (just click on the boxes). Team Finland won the architecture award at the competition (more info on the house here), and there's loads of info on the University of Florida's traditional-looking but ultra-modern house here. There's also an in-depth profile of the University of Nottingham's house in current issue of Construct Ireland.

Sorry for the brevity here on a subject that deserves much more attention - we're getting down to the heavy work on the July issue of the mag, so updates to the blog and news section might be sparse over the next week or two. But we've got an exciting issue coming up, with profiles of a couple of stick-built timber frame houses (including one that is staggeringly air tight), a piece on the most sustainable way of dealing with ghost estates and an opinion piece by Bord Gais CEO John Mullins on the company's green plans. 

 

For your reading pleasure:

Open House 2010 Dublin Highlights announced: Irish Architecture Foundation

Solar assisted air conditioning comes to market: Treehugger

Slideshow of the Cooper-Hewitt national design awards in the US: Treehugger (some of the products and buildings are quite green)

Profile of the first legal third party appeal of a LEED (Leadership in Energy and Environmental Design - the leading US environmental rating system for buildings) rating: Green Building Law

Profiles of nine "near carbon neutral" communities: Jetson Green

Solar PV integrated into ceramic roof tiles: Jetson Green

Sustainable Industries' top ten green building products of 2010: Sustainable Industries

Altering clocks in winter "could cut carbon emissions": Energy Savings Trust

Dubbed the Infrax building, this is the new headquarters of the West Flanders Energy Company in Belgium, and I'm posting it for the simple reason that it's quite stunning and reasonably green. I've taken the info that follows on the building's technical features from the website of architects VK.

...The West Flanders Energy Company commissioned the building of a new high-quality office in Torhout, complete with a warehouse and storage space. WVEM wanted its new premises to be sustainable and have low energy consumption to underscore the example the company sets for society…

...The office building has three levels, with ground level extension used as a communal dining hall. The building covers 4800 m2…

…Extensive insulation of the building shell and the use of high-quality insulated glazing gave the entire building an overall insulation level of K35. The building is heated at low temperature by concrete core activation on the upper levels and floor heating at ground level. Small low-temperature convectors are used to fine-tune the temperature in each zone. The offices on the upper levels do not have lowered ceilings. In summer the concrete core activation provides very comfortable and energy-efficient cooling of high temperatures. The calculations for the design were produced using detailed comfort and energy simulations of the office….

...Soil was integrated in the design as a sustainable source of energy. A borehole energy storage (BES) field combined with a high-performance water pump provides basic low-temperature heating in the building in winter…

…At ground level the building has mechanical ventilation, while the upper levels are equipped with a hybrid ventilation concept, because for 60% of the office time a building can be ventilated naturally without compromising on comfort. A hybrid ventilation concept means the building is ventilated mechanically in winter and summer and naturally at other times of the year. The result is a significant saving of energy. Heat recuperation occurs in the central air group…

…The hybrid ventilation system has been integrated in an intelligent facade concept. This concept is a highly integrated design of architecture and engineering. The ventilation facilities have been integrated in a double facade system, comprising an insulated inner shell and a glazed outer skin. The cavity between the two can be drenched with outdoor air. Outside summer and winter, the cavity air heated by the sun is used to deliver fresh air to the offices by manually opening 'viewing windows’. 'Light windows' allow ample daylight to penetrate deep into the offices. The windows are set well back in the intelligent façade to shield them from direct sun radiation. What's more, the double facade structure provides better acoustic insulation between the busy ring road and the offices...

…Photovoltaic solar cells integrated in the facade provide the energy required to drive the primary pump of the BES field. This makes it possible to cool the offices by means of the BES field and concrete core activation without extra energy consumption. The offices have been equipped with energy-efficient lighting fixtures, complete with daylight control and presence detection sensors…

...The office building has been equipped with water-efficient sanitary furniture and plumbing to minimise the demand for water.  Rainwater captured on the roof is reused in the building to flush toilets and urinals. The parking spaces for cars are pervious. Water originating from the metalled surfaces is infiltrated on site in green basins integrated in the car park landscape.

Sorry for the lack of blog updates last week - I had some trouble with our blog software and a blog post I published seemingly disappered. Anyway, here's a quick round up of recent links to get things kick-started again, mostly courtesy of Inhabitat and Treehugger.

Database will detail money saved from green retrofits in New York: Inhabitat

World's fastest train rolls off production line: Inhabitat

Work starts on UK's largest prefabricated straw bale building: Inhabitat

Can we use biomimicry to design cities? Treehugger

Toyota working on electric vehicle with Tesla: Inhabitat

University of Nottingham unveils solar-powered house: Inhabitat

A profile of Finland's entry into Solar Decathlon Europe: GreenBuildingAdvisor.com (Construct Ireland previously profiled the US Solar Decathlon here)

Green roofs now mandatory in Copenhagen: Treehugger

The Olympic Stadium, London, under construction. Photo by tompagenet . 

I listened to Peter Bonfield, the chief executive of the Building Research Establishment, talking in Dublin last year about sustainability at the now-under-construction Olympic park in London. He was speaking at the annual conference of the BRE's Irish arm, and two aspects in particular impressed me: the amount of material being recycled, and the genuine efforts being made to ensure the facilities will benefit local communities in the long term - social sustainability, you might call it. For example, the upper half of the main stadium (above) is a temporary structure that will be removed after the games, ensuring it's not out of place in the surrounding community and that local people will feel comfortable using it.

Which brings me to an interesting video from the Guardian on the sustainable features of the Olympic park facilities.

If you want an alternative take on the social impact of the Olympics, read George Monbiot here and here .

In Novemeber 2008, George Monbiot wrote regarding the American "thinker" Sharon Astyk:


In an interesting new essay, she points out that replacing the world’s energy infrastructure involves “an enormous front-load of fossil fuels”, which are required to manufacture wind turbines, electric cars, new grid connections, insulation and all the rest. This could push us past the climate tipping point. Instead, she proposes, we must ask people “to make short term, radical sacrifices”, cutting our energy consumption by 50%, with little technological assistance, in five years. There are two problems: the first is that all previous attempts show that relying on voluntary abstinence does not work. The second is that a 10% annual cut in energy consumption while the infrastructure remains mostly unchanged means a 10% annual cut in total consumption: a deeper depression than the modern world has ever experienced. No political system - even an absolute monarchy - could survive an economic collapse on this scale.

 Astyk's essay can be found here.
 
Re-reading Monbiot's piece recently, it got me thinking about how much carbon would be emitted by a massive national insulation and retrofitting effort here in Ireland - by the manufacture and transport of the materials, the vans on the road etc. I'm not for a second suggesting this work shouldn't be done - it should and must.

 It's the only way to future-proof our buildings against energy insecurity and to help ensure they are responsible for producing as little carbon dioxide as possible - I'd much rather rely on a highly energy efficient building to keep energy use low than on consumer behaviour. And besides, there's an important comfort argument to be made here too - everyone would prefer a well insulated, warm home to having to reduce energy use even further in a draughty energy inefficient home.
 
But the question is, how do we keep the carbon footprint of retrofitting itself to a minimum? Is the key using as many locally produced, low embodied energy materials as possible? Or perhaps to ensuring batches of houses are done at the same time to ensure transport efficiency? As far as I can tell, nobody has really attempted to answer the question of how to minimise the carbon footprint of retrofitting, or done a thorough carbon audit of retrofitting work. Anyone?
 

The advantages of magnesium-based cement: GreenHomeBuilding.com

Frank Gehry's Dancing House, Prague. Photo by RyanGWU82.

Renowned architect Frank Gehry caused a a bit of a stir last month during a speaking engagement in Chicago. Asked about the role of green architecture and buildings in tackling climate change, he said: "I think the issue is a political one."

He went on to criticise LEED, the US's rating system for the environmental impact of buildings, for rewarding "bogus stuff", and added that the costs of green buildings are "enormous", and that "they don't pay back in your lifetime."

Treehugger has an interesting report on the response from architecture writer Fred Bernstein, who defends Gehry's criticism of LEED, writing in ArchNewsNow:

One example is CityCenter, the Las Vegas complex that contains more than 5,000 hotel rooms, plus casinos and shopping malls and restaurants and nightclubs - altogether, 18 million air-conditioned square feet smack in the middle of the Mojave Desert. I can't imagine a greater environmental disaster than this complex (which, in addition to requiring vast resources to build and operate, is designed to draw travelers from around the world). And yet it was awarded LEED Gold status.

What I found most interesting was Gehry's claim that the costs of green building are "enormous" - this is patently untrue. Construct Ireland has published numerous articles over the years that prove green buildings - or at least buildings that are quite green - can be built at little extra cost (see this project for example). Consider the mixed-use complex in Foxrock we featured  in the March issue of the magazine, which will be online shortly. It's built to an almost-passive energy standard and makes abundant use of green materials, but Seamus O'Loughlin of contractors Viking House told us his price was the same as that offered by conventional builders - who were planning to build to the 2005 energy standards - who also bid for the project.

Gehry has designed some of the most iconic buildings of our times, but I think his comments are reflective of a wider lack of understating among many architects when it comes to green building and architecture. Of course some have been building green properly for a long time, but many have only started to talk about sustainability as the term has become trendy in the last five years or so. While some have genuinely made the effort to educate themselves, others haven't and just throw the lingo around. I've spent hours browsing architects' websites looking for potential case studies for Construct Ireland, and though many talk a lot about sustainability and energy, when you get to the details they usually reveal a lack of in-depth knowledge about what green building really is. In fairness to Gehry, at least he isn't pretending to be green when he isn't. 

 

Knock yourselves out: 

US group offers to meet Ireland's wave energy targets: Irish Times

OMA Architects has created an ambitious proposal for a European-wide power network that it claims would reduce the conintent's carbon emissions by 80% by 2050. Check out a fascinating image gallery of the design here: Guardian

The Emilio Ambasz Prize for green architecture, top three: ArchDaily

Bill Gates donates $300,000 to cloud-seeding geo-engineering technology: The Times

Slideshow - the greenest of the winners of the Canada governor general's medals in architecture: Treehugger

Short profile of a passive house in the Wisconsin Woods: Green Building Advisor

Will fly ash be classified as a hazardous waste by the US Environmental Protection Agency: Green Building Law Update

I've been keenly waiting to see the finished Monte Rosa Hut in Swtizerland since I saw the first design illustrations, and the building is now finally finished. This Swiss mountain hut, a five-storey timber frame building on steel foundations, is designed to be 90% energy self-sufficient - it boasts an 85 square metre solar PV array with excess energy stored in "lead-acid accumulators". There's more details here and here. Photos courtesy of ETH-Studio Monte Rosa/Tonatiuh Ambrosetti.

 

Last week the American Institute of Architects announced its top ten green building projects of 2010. Pictured below is one of the buildings, the Omega Centre for Sustainable Living in New York. Jetson Green has a gallery  of all the buildings, while detailed information on all of the projects can be found here . 

Photo by Andy Milford

For your perusal:

A journalist re-designs his neighbourhood: Grist
Is the Passivhaus standard too inflexible for America? Treehugger
Solar plane takes first successful flight: Inhabitat
A few interesting green buildings: Wildlife Conservation Society HQ, Harpoon House, Maine low enegy house, Dairy barn converted into eco home, Guelph City Hall
Frank Gehry not a fan of green architecture, says the cost of green building is "enormous": Infrastructurist
Applying Passivhaus to a "centuries old" building: Green Building Advisor
How to sell green products to builders: Green Building Advisor
Sustainable 'superbus' under development: Energy Saving Trust (more here)
Best of green design & architecture, 2010: Jetson Green

Sorry for the prolonged absence - after the madness of the last CI deadline I took a week off, but normal service will resume now.

The following letter appeared in the Guardian a couple of weeks ago. Does Ireland need a green bank too, or are the big banks' 'green funds' enough? 

 

 
As it says on the tin. Full details here.

Just a quick update today, as the deadline for our next issue is approaching rapidly. Anyone interested in reading more about the pay-as-you-save programme launched in Britain yesterday should take a look at the official press release. The plans seem quite ambitious - ambitious enough to make you wonder if the amount of work that's being planned can be done properly in such a short space of time. Are the skills and expertise available and ready?

These figures caught my eye particularly:

The strategy will be implemented in a three stage plan:

• To insulate 6 million homes by the end of 2011
• To have insulated all practical lofts and cavity walls by 2015
• To have offered up to 7 million eco upgrades by 2020; all homes to have smart meters.

According to the Guardian yesterday:

 

 

A bumper bunch of links today:

Video of Bill Gates talking about 'zero carbon' at the TED conference: TED
World's tallest building closed indefintely: Archinect
50 "must read" green engineering blogs: Top Online Engineering Degree
Passivhaus renovation of a Victorian terrace house: TreeHugger
Are the days of the cul de sac over? Treehugger
Looking at lights from space - a sign of progress or failure? Treehugger
Norway to build world's largest wind turbine: Inhabitat
The coming renaissance of electrical contractors: softwareadvice.com
Would you live in a shipping container? Inhabitat
Is the Living Building Challenge the toughest green building standard in the world? Jetson Green
UK boiler scrappage scheme a "success": Energy Savings Trust
Barack Obama's $5bn green home gets off to a slow start: Guardian
Loft insulation - Australia's burning issue: Guardian

...and lastly, officials in Tysons Corner, Virigina are thinking of letting developers build at higher densities if their buildings are greener - a concept known as 'planning gain', and something I wrote about in my first ever article for Construct Ireland.  See Green Building Law Update for more.