Net Zero Home Build: My Biggest Regret Building My New House. There are a lot of different paths you can take to get to a net-zero home. Everything from passive homes to earthships to modular and factory built houses. You can retrofit an existing building or you can build a new one. All of the options can make your head spin and there are pros and cons to each of them. In my case, I’m building a new, factory built net zero home with a lot of solar panels, which has been in the planning stages for a while now, but is scheduled to start construction very soon. I thought it would be interesting to share what I’m doing and why my wife and I chose the path we did. So let’s see how we came to our decision … and if I have any regrets so far.
In recent months, armed with the promise of reducing pressures on both budgets and the environment, home energy solutions have been thrown firmly into the spotlight amidst the rising cost of living crisis. However for Robert, his foray into renewable home energy began 30 years ago, and since then his house has been a playground to test a wide variety of sustainable technologies. Earlier this year he said goodbye to his last source of fossil fuel allowing his home to run carbon free and for extensive periods off grid. From Solar Panels, Tesla Powerwalls, MyEnergi, Zappi, Tepeo and Mixergy Tank and a good dose of insulation – Robert takes us on a tour of his home and spills the beans on his experiences as well as the home energy dos and don’ts!
The world’s first fully working “sand battery”, which can store green power for months at a time, has been installed by Finnish researchers. The developers said this could solve the problem of year-round supply, a major issue for green energy. Using low-grade sand, the device is charged up with heat made from cheap electricity from solar or wind. The sand stores the heat at around 500C, which can then warm homes in winter when energy is more expensive.
If current developments in plastic consumption aren’t curbed, at some point there will be more plastic in the oceans than fish. One solution could be the replacement of fossil-based plastics with plant based materials, that are biodegradable. A key material is Lignin, a class of complex organic polymers.
[avantium.com] – Company site
[wikipedia.org] – Lignin
[nl.wikipedia.org] – Avantium
[twitter.com] – “Bio Roads”, substituting 30% bitumen with lignin
[avantium.com] – Avantium and Roelofs construct the world’s first test road with lignin produced in the Netherlands
Float glass uses common glass-making raw materials, typically consisting of sand, soda ash (sodium carbonate), dolomite, limestone, and salt cake (sodium sulfate) etc. … The raw materials are mixed in a batch process, then fed together with suitable cullet (waste glass), in a controlled ratio, into a furnace where it is heated to approximately 1500 °C. Common float glass furnaces are 9 m wide, 45 m long, and contain more than 1200 tons of glass. Once molten, the temperature of the glass is stabilised to approximately 1200 °C to ensure a homogeneous specific gravity.
The molten glass is fed into a “tin bath”, a bath of molten tin (about 3–4 m wide, 50 m long, 6 cm deep), from a delivery canal and is poured into the tin bath by a ceramic lip known as the spout lip. The amount of glass allowed to pour onto the molten tin is controlled by a gate called a tweel.
Tin is suitable for the float glass process because it has a high specific gravity, is cohesive, and is immiscible with molten glass. Tin, however, oxidises in a natural atmosphere to form tin dioxide (SnO2). Known in the production process as dross, the tin dioxide adheres to the glass. To prevent oxidation, the tin bath is provided with a positive pressure protective atmosphere of nitrogen and hydrogen.
The glass flows onto the tin surface forming a floating ribbon with perfectly smooth surfaces on both sides and of even thickness. As the glass flows along the tin bath, the temperature is gradually reduced from 1100 °C until at approximately 600 °C the sheet can be lifted from the tin onto rollers. The glass ribbon is pulled off the bath by rollers at a controlled speed. Variation in the flow speed and roller speed enables glass sheets of varying thickness to be formed. Top rollers positioned above the molten tin may be used to control both the thickness and the width of the glass ribbon.
Once off the bath, the glass sheet passes through a lehr kiln for approximately 100 m, where it is cooled gradually so that it anneals without strain and does not crack from the temperature change. On exiting the “cold end” of the kiln, the glass is cut by machines.
– Embodied energy float glass: 15.9 MJ/kg or 4.4 kWh/kg
– Standard glass used in horticulture: 4 mm, unhardened
– 1 m2 glass of 4 mm thick weighs 10.0 kg
– Embodied energy (EE) of 1 m2 glass of 4 mm think is 44 kWh
– EE energy greenhouse glass Sundrop Farm: 200,000 m2 x 44 kWh = 8,800 MWh
– 1 liter of petrol = 10 kWh, 1 m3 petrol = 10 MWh.
– Glass production Sundrop Farm greenhouse = 880 m3 petrol
– Take a factor of 1.5 to account for oblique roof: 1,320 m3 petrol
Do we need fossil fuel for the production of glass? No:
[mo-sci.com] – Are Electric Furnaces the Future of Glass Manufacturing?
In most places, it is still environmentally cleaner to burn fossil fuels in a furnace than to use them to generate electricity for electric melting. However, as renewables increase their contribution to electricity production, this situation will change. It also appears that improvements in energy efficiency of fossil fuel combustion technologies have leveled off. As emissions legislation kicks in and consumers increasingly demand materials and technologies that are environmentally friendly, there may be well a swing in glass manufacture from gas to electric energy. The other advantages of electric melting, such as better thermal efficiency and energy consumption, will also count in its favor.
[eurotherm.com] – The future for the glass industry is “all-electric”
The burning of fossil fuel as an energy source in the glass melting process results in unavoidable carbon emissions, and improvements to traditional technology have reached their efficiency limits. Moving to electrical heating methods has many benefits including improved energy efficiency, more flexible control and less combustion related emissions. The aim of this paper is to stimulate glass manufacturers into rethinking their existing melting technology and considering “all-electric” melting in the near future.
How much time does it take for a 6 MW offshore wind turbine to generate the energy equivalent of 1,320 m3 petrol or 11,000 barrel of oil? Said wind turbine produces the equivalent of 32,285 barrel/year. So the answer to the question is:
Ecodorp Boekel is a sustainable living project, consisting of 30 climate-adaptive, climate-positive rental homes, 6 informal care homes, community center, knowledge and education center, workplace and offices, with opportunities for food and energy supply, ecological water treatment and sustainable businesses. The eco-village is being build since 138 days now together with ecological contractor Eco + Bouw and architect Huub van Laarhoven, financially supported by the Noord-Brabant province and the EU.
In 2015, the citizens of Holzkirchen, Bavaria-Germany, decided 17-8 to build a geothermal heat & power station.
Investment: 40 million euro.
Operational: early 2019.
Hot water production rate at 150C: 50 liter/s, from 2 wells at a depth of 5000 m.
Power generation: 3.4 MW, organic Rankin cycle.
Electricity guaranteed for 20 years at 25 cent/kWh.
Yearly income: 6 million euro.
Payback time investment: 20 years, after that “free clean energy”.
Balance heat-electricity generation is not fixed but adjustable.
Many say: better this than ever more wind turbines.
The operation now works successful and ambition is growing to expand to other municipalities. It looks like Holzkirchen just created yet another renewable energy option, apart from solar, wind, biomass and hydro. Holzkirchen is already thinking of drilling a third borehole. Expect this example to have many followers.
[gw-holzkirchen.de] – Geothermie, project stite
[yale.edu] – Aiming for Climate Targets, Germany Taps Its Geothermal Potential
[merkur.de] – Geothermie Holzkirchen: Neue Bohrung mit neuen Partnern?
[merkus.de] – Geothermie ab sofort in Betrieb
[merkur.de] – Geothermie Holzkirchen: Neue Bohrung mit neuen Partnern?
[wikipedia.org] – Organic Rankine cycle
1. Heat generation, heat exchangers. Oil & gas backup present
2. Cooling
3. Well and pump, 550m below the surface
4. Turbine generating electricity, pumped in the grid for 25 cent/kWh
5. Control center
In our view, photovoltaic thermal hybrid solar collectors (PVT) are one of the most underestimated renewable energy harvesting solutions in places where space is rare and expensive. Think countries like the Netherlands. In a solar panel, a typical 20% of the solar radiation is transformed into electricity. In an isolated black flat plate solar thermal collector, the absorption rate is near 100%. In oractive typical values are: 250 kW electricity plus 400 kW heat, and operating with 80% overall conversion efficiency. In a hybrid PVT-panel/collector the photo-electric and thermal functions are combined in one. In the examples presented here, the thermal collector functions as the source for a heat pump. This is an alternative to more conventional solutions as extracting heat from a much colder source like 10 Celsius soil. The roof rather than the garden, so to speak.
In the Netherlands it is no longer allowed by law to build new homes with a natural gas connection; hence tens of thousands of new homes every year come with a heat pump installed. The battle for the most advantageous heat source for the heat pump has been ignited: soil, air or PVT-roof. May the best solution win.
Cheap printed home from Austin, Texas. Real promise for the third world.
3D-printing opening up the possibility that by the turn of the century, most people on this planet, including territories such as Africa, India and the Philippines, could live in a stone, 3D-printed home, connected to sewage, a local solar power source.
The financial and technological push for this should come from Eurasia, in return for a rigorous birth control program: 2 children and not more. The way to provide these territories with the financial means to pay for it, is to integrate them in a global energy scheme. Sunny territories with an abundance of cheap labor should provide a sizable chunk of the planet’s future hydrogen needs.
[bbc.com] – The world’s first family to live in a 3D-printed home
In Eindhoven in the South of the Netherlands, houses are to be printed, intended to be sold on the regular commercial market. The innovation is that the homes will have several stories (English subs))
[cnn.com] – A small community of 3D-printed concrete houses is coming to the Netherlands
Europe’s first 3D-concrete printing factory opened in Eindhoven. Interesting is that traditional wooden molds are no longer necessary and that far less cement is being used. Steel concrete enforcement can be printed too.
Very large-scale 3D-printing project in Den Helder in the Netherlands, where a shabby building from the seventies is being upgraded with ca. 1,200 new 3D-printed concrete elements of 2 to 12 m2 each.
The road-dual purpose project SolaRoad in the Netherlands still exists. The idea is to combine the traditional transport function of the road with generating solar energy from panels on top of the road structure. The panel is the road, so to speak. It began with a bicycle path, now bus lanes are next. The glass cover layer has been replaced by synthetic material. The rationale behind this project is that in the Netherlands, space is rare and expensive. Hence the idea that dual use of road surface could be economical.
Dutch language video
[solaroad.nl] – Project site
[tno.nl] – Nieuwe fase SolaRoad: ook autoweg gaat elektriciteit opwekken
[deepresource] – SolaRoad Followup Project (2018)
[deepresource] – SolaRoad Project Still Alive (2017)
[deepresource] – SolaRoad Project Update (2016)
[deepresource] – SolaRoad Operational (2014)
[deepresource] – SolaRoad Finally Launched (2014)
[deepresource] – SolaRoad (2013)
DeepResource 