Denmark has long served as a world leader in clean energy and industrial symbiosis. For example, they were the first country worldwide to announce their transition to a clean growth economy entirely independent of fossil fuels by 2050.  In 2019 CSI helped lead a bipartisan delegation of state legislators from Washington on a learning tour, with i-Sustain, and funded by Scan Design Foundation, in Denmark to explore how industrial symbiosis might apply here in the Pacific Northwest. Here a couple of the major highlights:



















Kalundborg Symbiosis

This small town pioneered the concept of industrial symbiosis some four decades ago, and has adapted and grown it over time into the world’s leading model for industrial symbiosis innovation. Today the Kalundborg Symbiosis is a resource partnership between six private companies and three public operators, dedicated to full resource utilization, including water, energy and material. Begun as a collaboration of several private companies, in recent decades the municipally-owned Kalundborg Utility has evolved into the heart of the local Symbiosis. It is a multi-utility, with 80 employees, supplying 50,000 customers with several important services, including district energy, drinking water, process water, cooling water, and wastewater treatment. Today, the Symbiosis features 22 distinct resource agreements between facilities, each delivering mutual economic and environmental benefits. In a city of just 17,000 people, the Kalundborg Symbiosis is generating $28 million in yearly economic value, and at the same time reducing climate pollution by over 600,000 tons a year.

Solrød Biogas:

Denmark is investing heavily in renewable natural gas (RNG). Solrød Biogas utilizes over 190,000 tons of biomass feedstocks a year from several local industry and municipal waste streams to produce clean electricity and heat, organic fertilizer for farmers, and other key products. Their biogas digester utilizes a variety of local organic waste sources, including lemon-derived pectin and carrageenan from CPKelco (60%), eluate (biotech waste from lactic acid production) from ChrHansen (13%), biopulp (22%), manure from local livestock farmers, and seaweed overload from local beaches. The plant employs 15 full-time employees, and in 2018 delivered net greenhouse gas savings of 43,700 tons. They refer to their model as the “triple helix” partnership: the municipality has regulatory authority, companies benefit economically, and institutions for higher education are invited to conduct research and development. 

Billund Biorefinery:

Wastewater treatment plants can actually serve as integrated community biorefineries that process multiple organic waste streams to generate multiple products of value. Denmark’s Billund Biorefinery, owned by the municipality of Billund, is a model. The utility taps wastewater, organic wastes from local industry and agriculture, and the organic fraction of the municipal solid waste stream to produce energy and clean water. It produces 1.7 times the energy consumed in company operations -- both heat for the local district system and electricity for the power grid – as well as 4,000 tons of clean fertilizer products a year.

Fors A/S Municipal Integrated Utility:

Fors is a public, not-for-profit multi-utility company responsible for the distribution of water, district heat, wastewater, and waste/recycling for about 190,000 customers in Denmark’s Holbæk, Lejre and Roskilde Municipalities.  Fors actively supports a local business networking forum, which it has leveraged to organize industrial symbiosis relationships by uncovering partnerships with businesses on projects with a strong business case for both the business and the utility. They have formed value-generation partnerships with a variety of local businesses and industry, resulting in new industrial symbiosis, including:

  • Recycling rooftop filling waste from (tarpaper) from Fors into asphalt at another firm;

  • Galaxe Gluve produces lightweight concrete by blending in recycled polystyrene from Fors’s collection (MSW). This replaces gravel in concrete w/lightweighting benefits. Galaxe Gluve now picks up this material at no charget to Fors.

  • Recycling discarded plastic (MSW + commercial) from Fors into new plastic collection bins for Fors;

  • Recovering excess heat from a liver pate manufacturer for use by the local district heating system.

  • Sewer heat recovery from the utility to its district heating system

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