Apr 12, 2015: Sand Wars, Floating Solar Farms and other Fun Stuff.

Sand Wars… (not the happy, summer, beach kind).

For those of us who are concerned about the impacts our building choices have on people and the planet, there are so many things that we just don’t think about or hear about. Here’s a new one…  a friend from the states just sent me this article about the Deadly Wars Over Sand that are going on around the world. The article claims that after water and air, the thing that humans consume most is sand… who’d have thought it?

I suppose it makes sense when you think about all the ways we use sand: for concrete, bricks and mortar; as the basic ingredient of glass, silicon chips and solar panels; and in a thousand other products… As it turns out, in many places in the world, the right kind of sand is in very short supply and people are getting desperate to the point of killing for control of sand resources.

For me this is yet another reason to find alternatives to standard concrete in building construction. I have read studies that claim that concrete production consumes up to 10% of the world’s resources annually. Cement manufacture is incredibly energy intensive; mining for limestone, aggregate and sand consumes thousands of hectares of land and vast amounts of energy worldwide; and transporting both the heavy raw materials and the ready-mixed concrete to where it is needed also requires an enormous amount of energy and resources.

Alternatives to Concrete

The LEED Platinum Missoula Federal Credit Union, Russell St Branch in MIssoula, MT.

The LEED Platinum Missoula Federal Credit Union, Russell St Branch in MIssoula, MT.

All of the concrete in the building is made from 100% recycled glass and flyash.

All of the concrete in the building is made from 100% recycled glass and flyash.

 

 

 

 

 

 

 

 

 

 

 

 

Back in 2008-9, when I lived in Missoula, Montana, I was greatly privileged to be part of the team that designed and built the Missoula Federal Credit Union’s Russell Street Branch building. At the time it was only the second building in Montana to achieve LEED Platinum certification. This meant that the building had exemplary environmental and sustainability goals which you can read about at the link above. The most impressive thing about the building for me was that (as far as we know) it was the first modern commercial building in the world to be built with no portland cement. In fact, all of the ‘concrete’ in the building (including the precast exterior wall panels, interior posts and beams, and the cast-in-place polished ‘concrete’ floor and foundations) were made with a mixture of recycled glass and flyash. Flyash is a waste product from coal-fired power plants that is piling up in huge quantities around the world and no-one knows what to do with it. As it turns out, it can be used (sometimes after secondary treatment) as a binder to replace portland cement in concrete. In the MFCU building we also replaced all of the aggregate in the ‘concrete’ with a mixture of coarse (to replace the gravel) and fine (to replace the sand) crushed recycled glass. So there is NO concrete or portland cement in this entire building (although there was a bit used in the landscaping around it) and all the material used instead was recycled.

The coolest thing about this building for me is the way it sparkles as the sun reflects off the glass in the wall panels and the polished floor in the main lobby. Every time I rode my bike past it I would feel a surge of pride and hope knowing that we CAN find radically different ways of doing things that greatly reduce our impact on the planet, work well, look great and tell a fascinating and hopeful story.

Floating Solar Farms

On another hopeful note, I read this week about a proposed 350MW solar farm in Brazi that will float on the surface of a hydro-electric dam. What a simple, obvious and brilliant idea! Hydro electric sites already have transmission lines running to their power plants so the solar farm can tie directly into the same grid connection. The land that is now underwater has already been lost so why not use the surface of the water to make solar power rather than building solar farms on unspoiled land somewhere else. AND, as the article above points out, the solar panels shade the water (which helps to reduce evaporation rates and algae growth). PLUS the constant temperature of the water helps to cool the solar panels (which makes them work more efficiently). It’s a win, win, win, win situation.

One not-so-hopeful thing I read in this article is that ‘In addition to the loss of habitat that occurred with its construction, it’s claimed that methane released from the massive reservoir, which covers 2,360 square kilometres, means the facility emits more greenhouse gases than most coal plants.’ It’s pretty scary to think that the decomposition of organic matter beneath the surface of the world’s dams could be producing far more greenhouse gas than is saved by the hydro power they produce. This is all the more reason to put floating solar farms on the surface of the existing dams to make more renewable energy and hopefully, help reduce the greenhouse gas problem.

As it turns out, Australia’s first floating solar farm is also about to be built at a waste-water treatment facility near Jamestown in South Australia. This will not only produce more than enough electricity to run the treatment plant but will also shade that water, reduce algae growth in the treatment pond and reduce evaporation by an estimated 90%.

Artist's impression of Australia's first floating solar farm

Artist’s impression of Australia’s first floating solar farm (source abc.net.au).

Solar Power for Small Businesses

Here’s an excellent article from Solar Quotes which asks the question; why do we not see more solar power systems on small to medium sized businesses when the return on investment is so good? Most businesses use the majority of their power during the day when the sun is shining. This makes solar power an even more attractive option for commercial buildings than for residential where most of the power is used at times when there isn’t much sunshine. Averaged over twenty years, solar electricity typically costs less than 10c/kWh and commercial electricity rates can be as high as 50c/kWh. Because of the low cost of solar power systems many businesses are able to invest in solar power and see an immediate reduction in costs (the repayments on the solar system are less than the savings in electricity) along with a return on investment of between 10 and 35%. One of the main reasons we don’t see more PV panels on the roofs of businesses (and dwellings for that matter) is because many of these buildings are rented. Landlords typically don’t see the benefit of investing in solar power systems because they don’t pay the electricity bills. This is starting to change though as renters become willing to pay more for premises (and homes) that have solar power installed. It will be interesting to see how people solve this puzzle in a way that encourages landlords to install solar power on rental properties. Once that happens we’ll likely see a massive increase in the uptake of renewable energy systems on rental properties both commercial and residential.

De-politicising urban infrastructure planning to promote deliberative decision-making…

Don’t you love academic language? Despite the jargon this is a very  interesting article from ABC’s The Drum about how Portland and Vancouver have been much more successful than Sydney or Melbourne at planning for population growth without increasing urban sprawl and all it’s associated problems. One thing the article advocates is to take the responsibility for planning the future of our cities away from our state governments. It points out that Melbourne is now in its fifth 30-40 year plan in five decades and that each successive state government undoes all the work of the previous one and starts again (sounds like our federal government doesn’t it?).

‘Both (Portland and Vancouver) have been able to maintain an urban consolidation boundary for more than 30 years, in part due to a governance structure that is based on local governments working together on a common vision, rather than having it imposed by their state government.

This has the additional benefit of de-politicising metropolitan infrastructure planning. Rather than priorities being completely revised after each state election, metropolitan planning outlasts both state and local government election cycles.

Both cities also have political cultures that promote deliberative decision-making between the private sector, governments and civil society. For instance, both have taskforces to end street homelessness, bringing together all levels of government with philanthropic and private sector contributions towards a shared goal.

Both cities have a goal of “complete communities”, with all residents having easy walking access to public transport, schools and health care (which are all sources of local employment). Both cities map access to this infrastructure, and then prioritise infrastructure spending in poorly served areas, along with prioritising affordable housing provision in well-served areas….

…almost half of the residents of central Vancouver walk to work, which cuts down considerably on living costs and improves residents’ physical and mental health.’

Which all sounds pretty sensible to me and a whole lot better than the sprawling traffic nightmare that our planners have made for us in Sydney and Melbourne.

Fossil-Fuel-Free Investments Showing Good Returns

This article from The Sydney Morning Herald talks about the excellent returns that the financial markets are seeing from investments that don’t support the fossil fuel industry (which is good news for the Divestment Campaign). Of course it is helped greatly by the fact that the Arabs are flooding the market with oil and driving fossil fuel prices down to very low levels.

‘This study proves that fossil fuel divestment is not just morally right, it’s financially prudent, too,’ 350.org Australia campaigns director Charlie Wood said. ‘It shows fossil fuel stock are actually performing worse as we move forward. We’re listening to Bernstein, Goldman Sachs and HSBC, who are all saying coal has entered a structural decline, we’re not going to see it pick back up.’

If you haven’t already considered getting out of fossil fuel investments (which I’m proud to say my entire family has done) now might be time to think about it.

Reader Feedback

Glenn from Bundanoon likes to get right into the details of things. So if you’re like Glenn, below are some specific questions about the Greeny Flat with my answers in CAPS.

‘Have been pondering the greeny flat design for a while,  I know the site limited the east west length so the north south depth had to increase reducing solar penetration(had the same compromise with our studio). Wondered

  • why,with such a small footprint you gave up so much floor space to internal walling and corridors? THAT WAS MUM’S CHOICE. I INITIALLY PREFERRED A DIFFERENT DESIGN BUT THIS IS THE ONE SHE WANTED. AS IT IS THOUGH, I FIND THAT THIS DESIGN WORKS ALMOST PERFECTLY FOR CINTIA AND I.
  • why have such a large internal air volume relative to the area of floor available for solar heating? would be nice and warm if you sat on a swing up near the roof apex. ONCE AGAIN, MUM’S CHOICE. I ADVOCATED FOR A TRUSSED ROOF AND FLAT CEILING FOR THAT VERY REASON BUT SHE WANTED THE HIGHER CEILING. INTERESTINGLY, I’VE TESTED THE TEMPERATURE AT THE APEX AND AT FLOOR LEVEL AND THERE WAS NO DIFFERENCE. I CAN’T EXPLAIN WHY BUT THE TEMP AT THE TOP WAS THE SAME AS THE TEMP DOWN LOW IN WINTER.
  • why run an exhaust fan constantly when moisture is not being generated constantly? pulling more cold outside air in than really needed for a healthy atmosphere. GOOD POINT. I SUPPOSE A BETTER OPTION WOULD BE TO CONTROL THE EXHAUST WITH A HUMIDISTAT. AS IS, I MONITOR THE HUMIDITY MYSELF AND ADJUST THE SPEED OF THE CONTINUOUS FAN ACCORDINGLY.
  • why such a big PV system for such a small efficient house? not cost effective. HAVING NOT BUILT AN ENERGY POSITIVE HOUSE BEFORE I JUST TOOK A GUESS AT THE SIZE OF SYSTEM WE MIGHT NEED. COMPLETELY OVERSHOT IT, I ADMIT. BUT MY INTENTION FROM THE START WAS THAT IF WE HAD MORE POWER THAN WE NEEDED WE WOULD LOOK AT GETTING AN ELECTRIC CAR. I’D LOVE TO BE ABLE TO SAY THAT WE WERE ENERGY POSITIVE – HOUSE AND CAR! PLUS THE 3KW SYSTEM ONLY COST $4500. I JUST WISH WE HADN’T SPENT $6250 ON THE SOLAR HOT WATER SYSTEM.
  • does your sarking provide an effective thermal break outside the R 0.5 studs? most soft foams lose effectiveness when clamped under cladding. REMEMBER THAT THE INSULATED SARKING IS ONLY SQUEEZED AT THE VALLEYS OF THE CORRUGATED SHEETING SO PROBABLY 70-80% IS FULL DEPTH. BUT NO, 8MM OF SOFT FOAM DOES NOT GIVE AN EFFECTIVE THERMAL BREAK. BUT I WOULD ALSO ARGUE THAT THE INSULATING STRIPS YOU USED DON’T EITHER BECAUSE THEY STOP AT THE EDGE OF THE STUDS SO HEAT AND COLD CAN STILL GET TO THE WOOD. I’M NOT SURE WHAT THE MOST COST EFFECTIVE ANSWER IS FOR THIS.
  • What purpose does the external reflective surface on the sarking serve without an air gap to reflect heat into and vent away? SIMILAR TO ABOVE ANSWER, THERE IS AN AIR SPACE BEHIND MOST OF THE CORRUGATED CLADDING. WITHOUT BUILDING WALL SECTIONS AND TESTING THEM IT’S HARD TO SAY EXACTLY WHAT’S WORKING AND WHAT ISN’T. I’VE ACTUALLY CONSIDERED BUILDING AN R-VALUE TESTING BOX IN ORDER TO TEST SOME DIFFERENT WALL OPTIONS.
  • The metal roof is good for about 50 years, what happens when the outer skin needs replacing but the foam and inner skin are still good? Do you just roof over the existing materials? I SUPPOSE YOU COULD EITHER DO THAT OR TRY A ROOF PAINT. HADN’T REALLY COME UP WITH A GOOD ANSWER FOR THAT BUT MUM WANTED THE CATHEDRAL CEILING AND THIS SEEMED LIKE THE BEST WAY TO BUILD IT. HAVING TESTED MANY HOMES IN MONTANA WITH CATHEDRAL CEILING I NEVER FOUND ONE THAT WAS WELL INSULATED AND AIR-SEALED EXCEPT THE SIPS PANEL ROOFS.
  • In trying to be elder friendly the bathroom ended up not incorporating the usual accessibility clearances and features that let people age in place. Council LEP recommends provision for these features be made but the design did not address this, why did you elect to not incorporate these features as this, along with level egress are the main reason for buildings not serving occupants for their full lifespan? WE WEREN’T SHOOTING FOR WHEELCHAIR ACCESSIBILITY AND THERE IS PLENTY OF ROOM IN THAT BATHROOM FOR SOMEONE IN, SAY, A WALKING FRAME. WE PUT BLOCKING IN THE WALLS AND CEILING TO ACCOMMODATE GRAB RAILS IF AND WHEN NEEDED AND THERE’S ROOM IN THE SHOWER FOR A SEAT OR EVEN A CARER. AS FOR LEVEL EGRESS, WE INSTALLED THE ABSOLUTE MINIMUM NUMBER OF STEPS GIVEN THAT WE HAD TO EXPOSE THE EDGE OF THE SLAB FOR TERMITE PROTECTION PURPOSES. I ASSUME THAT THE TERMITE BARRIER SYSTEM THAT YOU USED WOULD HAVE ALLOWED US TO ALMOST COMPLETELY ELIMINATE STEPS AT THE EXTERNAL DOORS.

If you have questions of your own feel free to send them via our contact form.

2 comments to Apr 12, 2015: Sand Wars, Floating Solar Farms and other Fun Stuff.

  • Minwoo Kim

    Floating Solar Power Systems are wonderful Ideas. But, it’s very important to maintain effectively same direction and position on the water for floating solar plants. Because directional change of solar panels reduces electricity production. So floating solar plants also need the directional control mooring systems for their parked positions. Azimuth and position change of floating solar plants caused by wind, waves and external forces. Restoring Force Strengthened Mooring System for floating solar plants has been created in South Korea. This Mooring System generates Restoring Force immediately when floating solar plants are being rotated or moved on the water. Recently, Restoring Force Strengthened Mooring Systems have been used in South Korea. You can see the Restoring Force Strengthened Mooring System in Ochang Dam, South Korea. I N I WORLD

    • admin

      Thanks very much for the information. It sounds like an important consideration and the ‘Restoring Force Strengthening Mooring System’ sounds like a good solution. Andy.

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