Welcome – Renewable Energy Unbiased Thoughts and Opinions

Welcome – The first post is as a response to Phil Warner – a proponent of the ‘solar roof’ renewable and sustainable home heating system first outlined in 1944 by James Bryant in Brisbane, Australia – outlines of discussions on solar roof follow – Phil has promised to contribute over the next few weeks.

Solar Roof – Random Postings and Thoughts:

The SolaRoof uses no dark insulation – no shade cloth or insulation beneath the
inner glazing. The SolaRoof is highly transparent to PAR and the glazing
temperature (which is our thermal energy exchange surface area) is always within
a couple of degrees of the TMTemp. In the winter there is very low loss during
the mid day thermal energy collection period, since there is no deltaT -very
little difference in temperature of the inner and outer glazing. So, all the
heat of condensation is sponged up by the large liquid thermal mass with a
temperature gain per sunny day that is small – say 2C to 4C only and losses on
cold winter night of 1 to 2C when we have a 30 inch bubble cavity. So, we have
low demand for conventional energy during the heating season.

 

Dual Solar – Thermal store houses:

1.  Houses tend to be much better insulated than even dynamic foam buildings.  They don’t gain nearly the energy in summer that a greenhouse does.

2.  Modern house contstruction is based on, what? a 3 hour air exchange through heat recovery ventilators.  Not a 90 second air change. 

Now admitedly I’m comparing super efficient houses to standard greenhouse.  But we’re looking at a performance gap of at least two orders of magnitude.  While a completly active solar green house is a final destination, I don’t think we will achieve it in one step.

That said:  The dual thermal store is a clever enough idea, that partitioning your thermal store makes sense, as it is a tricky retrofit.

Putting a pool under the greenhouse seems costly.  In effect you are making either a swimming pool, or a full basement, combined with an earth roof.

Seems to me, you might be better off building on a lake.

Or building by a lake.  While a swimming pool is expensive dugouts cost on the order of a buck or so per cubic meter.  You need cooling only for the summer.  What are the thermal characteristics of a 15 foot deep dugout covered with white silage film plastic?  Remove the film in fall.  Circulate water from the dugout over the top of the ice all winter long.  By spring you have a pond that is mostly ice.  Ponds here are heated by both sun and wind but even by the end of summer, the water is still only about 70F.  Shielded from the sun, I bet it would be 50 degrees.

In winter then you need to scavenge heat.  So you only need to incorporate one thermal store into the building.  It can be smaller, and doesn’t need to be the entire subfloor.

***

In initial construction, there may be merit in NOT tightly integrating systems.  Nick has a bunch of good articles on his web site of the concept of ‘solar closets’  well insulated structures that get water very very hot, using barrels of water for storage.

Perhaps this becomes the north wall.  Building above ground is generally cheaper than building below.

***

One of the concepts I’ve been having trouble with in the dual store system is timing.  You want one store of heat at a high temp for night time heating.  You want one store at a low temp for day time cooling and dehumidification.

Using the water film cavity model, would someone walk me through the cycle?  I’m having trouble figuring out when the cold store is rechilled, and the hot store re-warmed, AND dehumidification is still happening at the right times.

***

Basic frame and film for a green house runs on the order of $4 per square foot.  Price with conventional sets of addons ranges from 7 to 12 bucks a square foot depending on how fancy you go.  Heating/cooling costs vary by climate, but I’ve seen figures of 3-5 bucks per square foot per year.  A neighbor of mine running two crops of seedlings per year in 7 40 x 150 green houses (42000 square feet) said his heating bill averaged $20,000 per month for his January-April crop.  And that was when natural gas was 20 cents a therm.

However the largest single operating cost is labour.  We have a coal generating station that offered free hot water (pick your temp from 140 F down to 40 F) to either fish or greenhouse operators.  (The amount of hot water:  3 GW.  Right now they use a 3 square mile lake to cool the water.  It’s enough heat to heat over a square mile of double film greenhouse space even at our winter temps of -40.

While various people looked at the offer, they figured that it would cost too much to bring labour in. Greenhouse jobs pay $10/hour here — 2 bucks over minimum wage.  You don’t drive far for a low wage job.  The fish operation was closer to being viable — it had a higher value of product per man hour, and some processing could be moved to a nearby processing plant.  But still it wasn’t good enough.

For Solar greenhouses to make a go economically, they have to be cost neutral with conventional greenhouses in no more than 5 years, and 3 would be better.  That is, the energy savings at the end of 3 years needs to pay for the difference in construction costs.  If my recollection of energy figures is correct, then 3 years energy is on the order of $12/square foot.

Can you make a solar system greenhouse that costs no more than $12 to $20 (3-5 years) more than the cost of a conventional greenhouse?

People in the horticulture business tend to be conservative.  They have enough unknowns dealing with the interactions of plants and light and water and chemicals and bugs and weeds, and disease.

 

Bubble Windows Debate

James Farham from the A.N.U. physics dept. (http://physics.anu.edu.au/) advocates ‘bubble windows’ as part of a solar powered , eco home – here is a fascinating article he came up with.

Given:
* a bubble tube floating on the surface of a soap solution can generate bubbles with reasonable efficiency.
* a fan that can operate that bubble tube quietly

Would it be reasonable to make bubble-windows?

e.g. build a window like an acquarium.  Make it as thick as the wall.  Put 2″ of bubble solution in the bottom, float your bubble tube in it, and have a small fan that moves air from the top of the cavity through the bubble tube.

Most twin pane windows are little better than R2.  You can make this a bit better by filling the interwindow space with argon, but everything I’ve read says the argon is gone (it ar-gone!) in 5 years.

A 6″ thick bubble filled space is something like R6, possibly more depending on who’s statistics/lies you believe.

In operation it has a very small heat store.  So the system as a whole will be the average of indoor and outdoor temp, yes?  This will mean that by the time temperatures outside get to -20 C, then the entire solution supply will freeze.  Possibly a good idea for zone 5, not for zone 3.

 

Yes, this works well – any shop with a compassed air supply can also use such an
approach to building a self contained bubble window with less cost and thereby
investigate the R-value of bubbles. I did this type of experiment in London
years ago with friends at a an engineering firm. Yet I saw no follow up to
determine the R-value. I visited the national construction research agency of
the UK called BRE (Building Research Establishment) to discuss action on high
R-value windows – nothing happened to follow up. These public agencies around
the world are avoiding the determination that such very high insulation value
windows can be constructed – not with costly, exotic technology but with simple
liquid bubble methods that are low-cost and provide 10x more results than the
best of the high tech windows.

When do we find some Universities (mechanical engineering schools) who will
cooperate to generate the data and verify (multiple replications of results) the
insulation benefit. Automotive air blowers work good for this purpose. What is
this idea for a floating bubble generator pipe or duct?

I envision the bubble window of this type to use a blower with a snorkel to the
top of the window cavity. The bubble window will sit into the wall opening flush
to the outside wall but extending (in thickness of the cavity space) into the
room where there can be a built in reservoir in the lower part of the window.
Depending on design this soap liquid reservoir would be supported at its base on
the floor. In this way the liquid is away from the exterior cold, behind the
insulated wall and the bubble cavity is made thicker with an insulated framing
method to assure the effectiveness of the insulation at the edge of the bubble
window. Of course it is advantageous that this window is large to reduce the
effective cost per square foot of the system. If it is a window wall then it is
useful to implement a bubble re-circulation path for true control of bubble
regeneration and destruction.

The liquid reservoir – in its position within the room is where a conventional
radiator would be located and so is not taking away floor space while giving
additional effectiveness to the bubble window. And, not only can the bubble
window insulate, it can also incorporate a radiator element with connection to a
hydronic cooling/heating system that can maintain the bubble window reservoir at
a set cool (for the summer season) or warm (for the heating season) temperature
by connecting to the building heating/cooling.

I would love to see a floor to ceiling bubble window that provides much light
and is as super insulated as the best wall. This is using two single glazing
layers – so it is not technically difficult to build. Please, those who build,
report your results to encourage others!

jfarnham@physicsanu.gov.au

Integrated Sustainable Building In The A.C.T.

There are some very promising developments in the A.C.T. regarding new home construction focusing on integrating ‘sustainability’ into their design and building processes

Recent History Of Sustainable Practices in The A.C.T.

. This has long been overdue. In the last 15 years or so in Canberra we have seen a ‘piecemeal’ approach to building environmentally sustainable housing. The A.C.T. Government, to its credit, has, in a fairly ad-hoc manner introduced many measures to assist existing homeowners do their bit for the environment. These include measure like:

  • Waster recycling

  • Green Bins

  • Rainwater Tank Subsidy

  • Rainwater recapture programs

  • solar power subsidies (State and federal)

  • Insulation subsides (good and bad!)

Emergence Of ‘Green Builders’


The last 2 years has seen a number of Canberra building companies spring up who offer an ‘integrated sustainable’ design model to their houses. I spent a few hours at such a Canberra building company on Monday. Green Broker uses the approach of project management to bring together architects,interior designers and sub contractors to build new homes that offer options of sustainability from the design end up, meaning from the moment the architect starts designing he can integrate solar panels, solar hot water, rainwater management, home orientation and building material selection, right into the design.

The Financial Benefits Of This Model

Upfront costs on the above measures typically add around 3 percent to the overall cost of the new home. The payback period, which do not include ‘environmental payback’ are typically less than 4 years. Analysis of reduced heating and cooling bills along with water usage reduction shows that the integration of these technologies at design stage actually positive yield cash flow benefits in year 6 or 7 for an average household.

Further details:

http://www.actpla.act.gov.au/topics/your_say/advisory_panels/act_architects_board

http://www.canberragreenbuilder.com.au/

http://www.yourhome.gov.au/technical/fs21.html

Solar Power Outlook in Australia 2013 / 2014 – Abbot Government

With the polls showing a Liberal national Government is likely to win by a landslide in the recently announced September elections and the Greens looking like loosing 2-3 percent of the primary vote the outlook for solar and wind as worthy inputs into grid supplied electricity in Australia is looking (possibly) less positive. With the Coalitions vow to scrap the carbon tax, the ALP’s 20 percent renewable target by 2020 is possibly the next ‘green’ initiative under threat. Tony Abbot - Coalition Renewable Energy Policy

Solar power has been blamed by many in the Coalition as the major contributor to electricity price rises. This is quite inaccurate as only 8 percent (Qld. being the most recent example) can be attributed to solar panels installation. The following article *Reference http://www.miningaustralia.com.au/news/report-says-coalition-carbon-tax-policy-doesn-t-ad) is worth reading and casts doubts on the Liberal-National Party’s policy to scrap the carbon tax:

“According to modelling by research group RepuTex, scrapping the carbon tax without implementing other industry changes would put a stop to investment in Australia’s renewable energy sector.

As SMH reports, if the Coalition wins the next election it plans to cut the carbon tax and retain the renewable energy target (RET).

RepuTex’s associate director of research, Bret Harper says that the existence of the carbon tax is what makes renewable energy a viable investment option.

Without the tax $23 per tonne carbon price and the renewable energy certificate of about $32 per megawatt-hour, renewable energy is just not a realistic investment option.

“The carbon price is linked to the renewable energy target. For those who support the RET but not the carbon price, there’s a gap in the logic there,” Harper said.

Harper says that, given that the federal government has left the RET at 41,000 gigawatt-hours of electricity each year from 2020, between 2014 and 2020 the nation will need to increase its renewable energy capacity by about three times as much as it has in the past ten years.

So, if a future coalition government were to repeal the carbon tax it would also need to substantially increase the value of the renewable energy certificate to meet this ambitious RET. But as it stands, Coalition policy is to repeal the tax but leave other market conditions unchanged.

“The existing scheme has a penalty price, which is effectively a price cap. If you remove the support of the carbon price but you don’t adjust the cap, then you will not see the renewable projects being built,” Harper said.”

Adelaide Advertiser Solar Power and Environment Letter January 2012

22 January 2013 – Worth a Read at John Graingers letter to Adelaide Advertiser

Reading with interest your thoughts on the future for solar power in Adelaide and the environment movement and by connection, the planet. Looks like a few of us have separated from the main stage of the fray; I for one am back in East Gippsland where the forests are still being trashed for no good reason despite excellent campaigns from the early 1980s on. Forest campaigns taught me that politics and economics (of the neoliberal kind) drive governments and give corporations their power. And democracy is the stone of David compared to the excavators and bulldozers of the exploiters.

I had a go at politics and see how important it is that we are engaged there – as we are through the Greens – but Green politicians can only succeed in making real change if they are the tip of the iceberg of green activism. Its the iceberg that seems to have melted. A negative impact of a successful Greens party is that many activists now focus their efforts there – after all there are jobs as advisers, party apparatchiks and potential for election – rather than working for nothing or very little in environmental action groups. Yet another effect is that environmentally/socially justice inclined people are deserting other parties for the Greens, leaving them bereft of a critical inner voice. Interested in peoples’ views of these observations.

Like you, I watched Rio + 20 as an indicator of the times. First I noticed that the huge chaotic but effective NGO forums of the 1990s UN Conferences (environment, human rights, population and women) were absent – as a voice heard by people like me, at least. It makes me wonder whether the democratic and far-reaching tool of the internet is in fact reducing activism to online petitions and keeping up-to-date with the latest postings. Second, I saw that the words ‘climate change’ were hardly mentioned and, third, that the morphing of ecologically sustainable development to sustained economic growth was complete (See Monbiot).

In my work for my PhD on global environmental/population issues/reproductive rights and health I saw that the conservative voices of the Catholic church, in alliance with fundamentalist Islam could silence governments, as they did after the Beijing Women’s Conference in 1995. Such was their power that the Cairo + 10 and Beijing + 10 conferences were deliberately very small affairs so that there could be no backtracking on the texts of the Programs of Action. But Europe was always a strong voice for human rights and the environment. Not at Rio, according to the article below.

Unless women everywhere have access to good reproductive health services and the right and means to access them, we will have a growing population of people without the resources to feed and educate them for a better world. Along with inappropriate consumption patterns, that is the key to many of our environmental problems.

In Australia the media gave more attention to Gina than the Rio+ 20 discussions whereas in 1992, I had a scrapbook full of articles from page one and op eds on the environment in all the daily newspapers. I don’t see the daily papers any more but pretty sure it wasn’t front page news.

Contact: jgrainger@iinet.com.au

A.N.U. Australian Solar Institute Developing 20+ Percent Efficient Solar Panels

A.N.U. Solar Institute and A.C.T. Solar In High Efficiency P.V. Development

 

It is very pleasing to see the fantastic work of the Australian National University (A.N.U.) Solar Institute (http://sun.anu.edu.au/) and a local Canberra based solar company, A.C.T. Solar (http://actsolar.com.au/) in developing the next generation of high efficiency solar cells, particularly in the area of multicrystalline silicon wafers which offer screen based manufacturing processes and relatively high efficiencies and low manufacturing costs. In addition their research into silver very low mass and transparent solar p.v. technology is  cutting edge and a credit (again to Australian solar ingenuity). This  technology is used for the fabrication of low density high quality silicon solar panels and achieves high efficiencies in an extremely cost effective manner. The efficiency of the solar panels used in residential solar (see the A.C.T. solar panels Canberra website for details) has typically ranged from around 12 percent up to 16 percent on average. Increases of even 4 percent can make a huge difference in terms of solar viability in the renewable energy / low carbon industries and technologies like S.I.Y.I (solar impurity yield increase) aim to further improve P.V. efficiency through improvement in silicon impurity levels (see http://sun.anu.edu.au/defects for details).

It is a credit to a Canberra Solar Company and the A.N.U. to produce quality developments in solar P.V. technology. We watch with interest.

Industrial solar cell diagram - Courtesy A.N.U

 

James Farnham 17 October 2011 – Contact me here

Solar Power in Melbourne set to Decline?

Solar Tariff Slashed – Why??

 

Unbelievable – the Victorian Government has slashed their feed tariff to a measly 8 cents per kilo watt hour! (See http://www.dpi.vic.gov.au/energy/environment-and-community/feed-in-tariffs ). The thinking is that solar feed in tariffs are creating an unfair situation whereby the residents installing solar and receiving the provisional feed in tariff were being subsidised by non-solar residents of Victoria…. Go figure – the Government introduces a carbon tax to encourage a mover to renewable energy – solar power, wind power, hot rock, geo-thermal energy etc and then has the gaul to cut the feed in tariff that supports the usage of solar panels in Melbourne.

The Background to Solar Power in Melbourne

(From:http://mps.vic.greens.org.au/node/2422)

“The Victorian Greens policy is to move beyond coal and cut our emissions to zero-net as fast as we possibly can, but in any case no later than 2050 (with a minimum 40% reduction by 2020).  That’s our policy because its exactly what we need to do on a global scale.  It can’t be done without phasing out coal fired power.

To achieve this, we will use the Environment Protection Authority Act 1970 to license coal fired power stations and set a cap on their pollution.  There are fines and daily penalties in the Act for breaching a license, which in this case means emitting more greenhouse gases than your license allows.

Hazelwood is the oldest and most inefficient of the coal fired power stations.  It was meant to shut down in 2005 but the Brumby government extended its life.  We want to close it down in the term of the next Parliament. Under the conditions of the proposed Hazelwood licence, we will set a timeline to shut down each of the eight 200 megawatt units sequentially over four years.

The eastern Australian states, including South Australia and Tasmania, are connected by a Federally run electricity grid.  The behaviour of both supply (power stations) and demand across that grid are complex and interrelated.  However these is a lot we can do as a state jurisdiction to reduce emissions while ensuring a reliable power system at the lowest possible cost.

In order to fully replace Hazelwood’s current contribution to the grid, we need to substitute for 1200 megawatts of peak power supply/demand and over a whole year about 10,000 gigawatt/hours of electricity consumption.”

 

Ok – so the idea was to reduce reliance on the dirty brown coal fired power stations in the latrobe Valley. The introduction of solar credits and the Victorian solar feed in tariff was surely a step in the right direction – now we have a 180degree turn around and the proponents of solar power have seen their cause ‘ditched’ in favour of high carbon emitting coal fired electricity production. What is the rationale behind this – like i say – ‘do figure!”

 

solar power melbourne

Solar Panels - Is the future Secure?

Canberra Solar Community Development

There is a proposal to build an ‘experimental’ sustainable community 5km out of Kambah, Canberra A.C.T. to trial 100 percent solar power and solar roof concepts in supplying all of the energy and heating needs . One side of The Community Center will be covered by a geodesic dome 600 feet in diameter. Housing modules will each contain 30 units, 70 bedrooms, and 100 residents in a three story arrangement with a footprint of 120 feet by 175 feet. Four of these housing modules will be placed horizontally inside the dome to a depth of 40 feet and be interspersed with three housing modules offset at right angles to them and ending at a distance of 280 feet from the community center. There will be 90 1, 2, 3, and 4 bedroom homes in the remaining area between the community center and an encircling agricultural complex. Orchards and parks will occupy the areas not taken up by the homes and housing modules. An agricultural complex in the form of the tire on a bicycle wheel 160 feet in breadth will encircle the housing/orchard/park area. The village dimensions equate to almost 40 acres, upon which will be grown all food requirements for 3,000 people (1,000 full time residents and 2,000 day time visitors) with all energy provided by regenerative sources and everything (village trash, biomass, water, and human/animal wastes) recycled. I envision greenhouses, perhaps supplemented by hydroponics, as possible methods of food growth as well as fish farms and animal enclosures for whatever meat sources are most amenable to this environment, including but not limited to chickens and rabbits.

Working through the above dimensions, the agricultural complex will be just over 650,000 square feet with a solaroof being one possible covering.

 

James Rogerson wrote in the Canberra Times:

My approach is going to be to develop a basic concept sketch of the village and then take the conventional path and send out requests for proposals for various parts of the village including, but not limited to the geodesic dome, the community center under the dome (with an auditorium, retail outlets, business offices, restaurants, school, health center, library, meeting rooms, etc.), a standard housing module (30 homes, 70 bedrooms, 100 residents), single family homes (1, 2, 3, and 4 bedrooms), parks/orchards, an agricultural complex (including greenhouses, hydroponics, fish farms, and animal enclosures), regenerative energy supply, recycling facility, and athletic fields. I will then collect these various component parts into a comprehensive rough order of magnitude cost estimate for the entire village and then, hopefully by the end of the year, be in a position to begin a realistic search for financing.

 

I plan to begin the search with one or more unsolicited proposals sent to one or more U.S. Government agencies, branch out into funding requests sent to foundations, include a donation solicitation campaign among businesses and private individuals, and culminate in a search for housing sales using conventional real estate practices.

 

Classes of home buyers who might find this village attractive could include newlyweds searching for an inexpensive starter home, families looking for a protected environment in which to raise their children, the retired desiring a location to minimize their travel requirements for everyday living, those interested in sustainable living, and environmentalists seeking to minimize their carbon dioxide foot print.

(source http://www.canberratimes.com.au/)

 

Solar Shingles

A very interesting product from Dow Power House in the U.S. – Basically a roof tile that integrates photo-voltaic cells into roofing tiles. They claim the aesthetics,cost and incentives make this the next generation roof top solar solution.