News

In the construction industry, everything is starting to look a little greener – the windows, the lights, the plumbing, and the heating and cooling systems. So it should come as no surprise that engineers have been dabbling in a more eco-friendly version of insulation too. It’s commonly known as hempcrete, and it’s changing the way our buildings retain temperature and conserve energy.

What is Hempcrete?

Hempcrete is an insulation alternative that mixes industrial hemp fibers and binders that resemble concrete to serve as the protective envelope inside a building. It is a mix of hemp hurds and lime, but possibly also contains natural sand, pozzolans, and cement. Hemp is a key crop in Manitoba, and it is most commonly used there to produce oil and seed. Hemp is also commonly used to make fabric and paper.

Building experts have developed a method for mixing the leftover wood core with water and binders to form hempcrete. In recent years, hempcrete has been catching on as a building material in Europe, where hempcrete buildings stand ten stories tall. Today, it is also marketed under the names Canobiote, Isochanvre, and Canosmose.

How Hempcrete Works

The industrial hemp core has a high silica content, allowing it to bind well with lime. This material is lightweight – about a seventh of the weight of actual concrete. Not only can hempcrete be used in the structure of buildings, but it also acts as insulating infill between frames. Loads are carried by internal wood stud framing, making it a popular option for low-rise construction.

Environmental Benefits of Hempcrete

Many eco-friendly builders praise hemp as a material because it’s a fast-growing crop and it can grow well in both tropical and temperate climates. It’s also considered to be an eco-friendly crop because it absorbs carbon dioxide as it grows. Hempcrete is considered to be a more eco-friendly material than traditional insulation, which is made of hydrofluorocarbons and can actually produce potent greenhouse gases.

Construction Benefits of Hempcrete

Based on research findings, hempcrete has the ability to manage moisture inside walls and store heat energy.

“Hempcrete is used as an environmental barrier for providing resistance to heat transfer and managing moisture of the building envelope,” said Kris J. Dick, an associate professor in the Department of Biosystems Engineering at the University of Manitoba in Winnipeg and director of Alternative Village, its construction research facility. “Engineers and architectural designers practicing in the field of nonconventional material applications have clearly indicated a need for more design data regarding hempcrete.”

Hempcrete Testing

To test the durability and longevity of hempcrete in modern buildings, engineers have developed testing methods to evaluate its safety and efficiency. Alternative Village’s Kris J. Dick conducted research within a 23.8-square meter to compare hempcrete to traditional insulation in terms of energy, thermal and moisture performance. The results of his study indicated that the hempcrete provided a stable temperature inside the wall and that temperatures were consistent throughout the wall.

To broaden its mass appeal in the industry, however, more development and testing are needed to improve hempcrete’s structural strength. Experts are also beginning to consider other hemp-like natural materials that could be utilized for alternative insulation purposes as well.

Source: VIATechnik, LLC (via Linkedin)

More on biobased materials

Southern Company’s 100 MW Nacogdoches Generating Facility – which the company calls the nation’s largest biomass plant – is now operational and putting electricity on the grid in Texas.

The plant, which occupies a 165-acre tract of land near Sacul in east Texas, is fueled by non-merchantable wood waste. This is a combination of wood-based biomass fuels consisting primarily of saw mill or other wood mill production waste, forest waste, precommercial thinnings of cultivated trees, and diseased and other non-commercial tree species. There is also the potential for the use of urban wood waste, tree limbs and branches produced by storms and other non-commercial logging-derived biomass, Southern says. (more…)

Between biogas, wind and solar, Anheuser-Busch generates about half of its electricity from renewable energy to make beer at its Fairfield, California plant.

The company is the largest in the US to use nutrients in its wastewater to make biogas, a process called bio-energy recovery systems (BERS).

They also recover the steam that heats boilers in the brew house to produce energy, in addition to retrofitting with more efficient boiler burners, air compressors and lighting systems.

They get another 4% of electricity from 6,500 solar panels that cover 6.5 acres. (more…)

Construction work has begun on a biogas plant in Bure, Switzerland that will provide heat for the local training barracks of the Swiss Army. The plant will use agricultural waste.

The plant is located in the French speaking Swiss Canton of Jura, which the company said boasts fertile soil and a lot of agriculture, and will be used to treat manure from the surrounding agricultural establishments and agro-industrial waste from the region, including liquid manure, dung, green waste, and grain waste.

The Bio Etique Energie facility will produce 370 kW of electrical output, while its entire heat surplus of 2.6 GWh will be used to heat the nearby barracks, which hosts up to 1400 trainees. (more…)

The doors have opened on a new biodigester in Wiltshire, UK following 12 months of construction and trails.

The anaerobic digester plant is, after trialling feedstocks for around four weeks, now fully operational and located at Bore Hill Farm.

‘We have now moved into the main building and the technology providers have completed all their pre-start testing work,’ says director Thomas Minter. ‘The end of the construction phase is a major milestone and having an operational plant to show after a year’s hard work by many local contractors is very rewarding.’ (more…)