One Tonne Life
Vattenfall

Tag: A-hus

Thanks and good luck, Lindells!

The family Lindell has now returned to their former life. We want to thank them for all time and commitment during the past six months in order to reach 1 tonne of carbon dioxide emissions. OneTonneLife.com will be left online so that is possible to browse the content published during the project time.

One Tonne Life is a project in which A-hus, Vattenfall and the Volvo Car Corporation joined forces with industry partners ICA and Siemens to create a climate-smart household.

Over a period of six months, the Lindell test family lived a climate-smart lifestyle with the aim of reducing their carbon dioxide emissions from 7.3 tonnes per year, which is roughly the average in Sweden, to a minimalistic one tonne. After an impressive final sprint, the Lindells crossed the finishing line at 1.5 tonnes.

The Lindells exchanged their 1970s home and their almost 10-year-old cars for a newly built, climate-smart wooden house from A-hus and a battery-powered Volvo C30 electric. Vattenfall provided renewable electricity, new energy technology and energy coaching. ICA and Siemens were industry partners for food and household appliances respectively. Method development and calculation of the family’s carbon dioxide footprint took place in partnership with the Chalmers University of Technology and the City of Stockholm’s environment and Health Administration.

Transportation and electricity consumption were the areas in which the family made the most progress.

Emissions from transport dropped by more than 90 percent, not least thanks to the fact that the family’s Volvo C30 electric was recharged with electricity sourced from hydropower. The family’s home from A-hus produced its own electricity and with renewable energy from hydropower, carbon dioxide emissions from purchased electricity were virtually zero.

Carbon dioxide emissions from accommodation were more than halved – and food is the third area in which the family made considerable progress. By not throwing away food and by making wise choices, the Lindells made a significant cut in their carbon dioxide footprint. Varying one’s choice of meat and eating more vegetables are easy ways for anyone to reduce food-based carbon dioxide emissions.

Viewed per category, the Lindells managed to reduce their CO2 emissions from transport by almost 95 percent, from food by 80 percent, from accommodation by 60 percent and in other areas by 50 percent. All told this means their CO2 footprint shrank by 75 percent.

Read more
Final report – detailed figures and comments from the family and the companies involved (PDF)
Calculation –  live climate-smart and save money each month (PDF)

The photo is taken June 13th after the official closing of the One Tonne Life project. In the middle Alicja, Hannah, Nils and Jonathan Lindell, surrounded by several of the persons who have been involved in project administration, media contacts, film and photography during the projekt. In the background the solar panel facade of the One Tonne Life house.

Follow the Lindell family!

During the One Tone Life project we document what happens in the life of the Lindell family on video. Here are all the webisodes (short episodes) that has been released so far. And as a bonus, the trailer for One Tonne Life. Enjoy!

From forest to finished house – part 3: the house factory

In 1960 Derome supplemented its sawmill business with building material sales. Today the company supplies construction materials and prefabricated building components as well as complete houses under the A-hus and Varbergshus brands. The A-hus brand covers prefabricated houses that can be picked straight from the catalogue, with the focus on design. In addition to sales in Sweden, these houses are also exported to the Netherlands, Belgium, Germany and Denmark.

The factory in which they are built is located at the very same site where the company was founded. Production is highly rationalised. A CAD system generates core data files with information for the production line, which uses the drawings to produce the houses. Every year, A-hus builds and sells 350 houses, that is to say about one a day. The Lindell family went to have a look at the house factory.

The family examine the production line together with Petra Cederhed of A-hus (on the right)…

…and Peter Mossbrant, President of A-hus (on the left).

Christian Axelsson of A-hus in discussion with Alicja about the plastic sheeting that serves as the “climate shell” of the One Tonne Life house.

Cross-section of a One Tonne Life wall, with the plastic sheeting inserted in two layers.

Hannah inspects the growth rings in the timber used for the facade.

The house walls are insulated.

Jonathan got to apply insulation strips to a window. He managed it well …

…as did Nils.

When the time came to try the nail gun, Jonathan focused on looking as cool as possible …

…while Hannah went all-out for enthusiasm …

…but wasn’t quite ready for the recoil!

Hannah shows the nails used in the nail gun.

Hannah watches as a window receives its final insulation treatment. This is the last step before …

…the module is ready.

From forest to finished house – part 1: the sawmill

While the Lindells were in Göteborg they took the opportunity drive south to Anneberg outside Kungsbacka, where A-hus has its production facilities. A-hus is part of the Derome Group, which traces its roots to 1947 when Karl Andersson started the first sawmill in Derome in the province of Halland. Today the Derome Group is Sweden’s largest family-owned wood processing operation. Here at Onetonnelife.se we touch base three times and follow the family on their visit to the sawmill and the factory that builds the houses.

The lumber is transported to a depot outside the building …

…and carried on a conveyor into the sawmill.

Inside the sawmill A-hus President Peter Mossbrant (standing between Alicja and Nils) spoke with enthusiasm about how sawn tree-trunks become ready-to-use timber.

The lumber enters the sawmill …

…and the sorting process begins. In his blog following the family’s visit, Nils writes about his fascination with the technology he saw at the mill. Mechanical old-school handling with toothed wheels blends with ultra-modern laser technology that calculates how each piece of lumber is to be cut to ensure minimum material waste.

The noise level in the sawmill is high and everyone had to use ear defenders inside the premises. Peter Mossbrant explains the sorting process to Hannah.

The lumber has now been transformed into timber.

Jonathan was very interested …

…as was Alicja…

…who is examining the final sorting process.

The finished timber is stacked outside the sawmill.

From forest to finished house – part 2: Biofuel

The Derome Group specialises in the wood processing operations and together with its subsidiary A-hus has a very strong pro-environmental profile. In addition to building low-energy homes such as the One Tonne Life house, the company also works in the following areas:

Wood – lobbies for increased use of wood in construction (as a building material wood is 10 times more climate-friendly than concrete)

Bio-energy – supplies biofuels (see below)

Solar heating – uses solar energy systems

Wind power – meeting all its electricity needs by 2012

Energy efficiency enhancement – to reduce consumption in production

Forestry – helps forest owners migrate to environmentally optimised forestry methods

During the Lindell family’s visit, Jonathan and A-hus President Peter Mossbrant size up the mountain of wood shavings produced by the sawmill.

Peter explains how the wood shavings from the sawmill are compressed to form pellets that can be used as fuel in the boiler.

Hannah, on the other hand, put the wood shavings to good use, improving her tan in the spring sunshine.

Webisode #8 “Trip to Gothenburg”

Heating system

In the One Tonne Life house, it is important to demonstrate that it’s possible to live energy-efficiently without compromising on either comfort or function. The Lindell family keep the heating going on cold days by utilising the building’s two separate systems. One consists of an energy-efficient underfloor heating system. This has been supplied by Uponor and features an intelligent control system called the Uponor Control System. This technology helps to efficiently distribute energy between the various rooms to ensure the maximum possible comfort while at the same time contributing to an energy saving of about 5%, thus also cutting carbon dioxide emissions.

Underfloor heating is only installed on the ground floor, where a cold floor would otherwise make a noticeable difference. On the first floor, the only heating source is heat distribution via the incoming air. This preheated incoming air heats up the first floor via valve-operated diffusers in the bedrooms and living-room. Before the air enters the house, it passes the ventilation unit which harnesses 84% of the heat energy in the outgoing air from the kitchen, bathroom and laundry room and uses this to warm up the incoming air. If this supplementary energy is not sufficient to maintain the required indoor temperature, an additional heating system linked to the accumulator tanks steps in. This takes place on exceptionally cold days.

These two heating systems are both based on solar energy, since they are both linked via the accumulator tanks to the house’s solar panels. If the sun cannot meet the building’s heating needs, for instance during the dark winter period, an immersion heater in the primary tank is activated. The primary tank is always in use and supplies the Lindells with heating and hot water throughout the year. When the sun shines most brightly, the house produces more energy than the family needs, and that energy is diverted to the building’s slave tank from where the stored energy can be used for a longer length of time throughout the year.

Christian Axelsson, A-hus

The house’s solar cells

The Lindells have solutions that will make things easier for them on their journey towards one tonne of carbon dioxide emissions per person per year. One of the challenges the family are facing is to reduce their electricity consumption. In order to further cut their energy usage, the One Tonne Live house will produce its own energy. Firstly via solar heating and secondly via solar cells that generate electricity. The electricity is produced by the house’s own solar cells which are fitted on the south-facing roof and façade. This electricity is used by the Lindells for cooking, recharging the family’s electric car and for powering other equipment at home. The solar heat that the house stores will produce most energy while the house is empty, for instance during the day while everyone is at work and school or while they are away during their summer vacation. Since solar heating produces a surplus of electricity, this will be fed into Vattenfall’s grid, with a corresponding amount of electricity fed back into the house when the sun is not shining.

The cells, made by Sulfurcell, are what are known as thin-film solar cells. All told, the One Tonne Life house’s 96 square metres of solar panelling will produce about 5000kWh/year in a normal year. Factors that affect actual output are how sunny the weather is during the year, the angle of the panels facing the sun, and the direction they face. The geographic location of the house itself is also a major factor – a house in the southern Swedish province of Skåne will produce more electricity than one in Norrland in the north of the country.

There are several different types of solar cell technology and thin-film is one of them. The advantages of the thin-film solution are its design and the fact that it creates a uniform, neatly integrated impression, as well as its price. This is an important consideration in order to recoup their cost over the years.

Christian Axelsson, A-hus

The house’s climate shell, part 2 – insulation, foundation and roof

In my previous text about the house’s climate shell I described the building’s structure. However, it’s not enough to simply have a good wall that features several layers of insulation – the insulation also has to be of high quality. The façade cladding and thermal insulation come from Isover, which supplied its most energy-saving insulating materials. The roof too features better than normal insulation. These materials are packed somewhat harder to increase their density, thus improving their thermal capability. The roof consists of a glued laminated timber beam that is eight metres long, 80 centimetres thick and 12 centimetres wide. This beam carries a number of joists that span the structure from the middle of the beam out towards the outer edges. We use this building method instead of traditional roof trusses to get extra volume to the rooms on the upper floor.

The foundation is a vital part of any house. In the case of the Lindell family’s house, it is built on a very special foundation that fulfils several functions:

1) It has to insulate the house from the ground
This is achieved with a 300 mm thick layer of Styrofoam that is inserted below the concrete. In the same way, the building’s edge beam, which supports the walls, is also insulated so it does not come into contact with the interior floor. This solution avoids the risk of thermal bridges via the floor.

2) It has to warm the house
The foundation integrates one of the building’s heating systems. It is a low-temperature waterborne floor heating system that has been installed to meet the Lindells’ comfort requirements and give them a pleasant indoor climate.

3) It has to be environmentally friendly
This is a difficult issue since the foundation is made of concrete. Wood is a construction material that is about 10 times more environmentally friendly than concrete, which means that the foundation accounts for a relatively large proportion of the building’s carbon dioxide footprint. In order to minimise the environmental impact of the foundation, we have reduced the amount of concrete in the foundation from the traditional 10 centimetres thickness to 8 cm.

Christian Axelsson, A-hus

Latest videos from the project

See all videos on Youtube

Latest photos from the project