| Claim | Source | URL | Supporting line or locator |
|---|
| ---|---|---|--- |
| Copenhagen's district heating began in 1925 as a small experiment in Gothersgade | DOI-2025 | see above | Lead: "The Copenhagen district heating system, which began in 1925 as a small experiment in Gothersgade," "today supplies almost the entire city" |
| HOFOR marked 100 years of district heating in Copenhagen in 2025 | HOFOR-AR25 | see above | PDF p. 4: "I 2025 kunne HOFOR fejre fjernvarmens 100-års jubilæum i København" |
| Over 100 years district heating moved from oil, coal and gas to largely sustainable biomass | HOFOR-AR25 | same | PDF p. 4: "Igennem 100 år har fjernvarmen udviklet sig fra at være baseret på olie, kul og gas som brændsel til nu i vid udstrækning at være baseret på bæredygtig biomasse." |
| The Copenhagen system dates to the 1920s | NYC-2011 | see above | p. 1: "the Copenhagen system dates to the 1920's" |
| Denmark faced several energy crises in the 1970s in which oil prices doubled; this led to the first Heat Supply Act in 1979 | DF | see above | "in the wake of several energy crises in the 1970s, where oil prices doubled"; "This lead to the adoption of Denmark's first Heat Supply Act in 1979 (revised extensively in 1990, 2000 and 2005)." |
| After the 1970s energy crisis a national heat planning program began; the 1979 Heat Supply Act let municipalities designate district heating areas and make connection mandatory for households | NYC-2011 | see above | p. 1: "After the energy crisis in the 1970's, a comprehensive heat planning program was launched in Denmark"; "The 1979 Heat Supply Act enabled municipalities to designate certain areas for district heating and make it mandatory for households to connect to district heating." |
| Heat Plan Copenhagen was introduced in 1984; the 1980s saw massive development of district heating and CHP in Copenhagen | NYC-2011 | same | p. 4, Timeline: "1984 Heat Plan Copenhagen introduced"; "1980s Massive development of District Heating and CHPs in Copenhagen" |
| Copenhagen's network was intensively developed in the 1970s to protect citizens and the economy from rising fossil fuel prices | C40-2016 | see above | "In Copenhagen, the district heating system was intensively developed in the 1970s as a way to protect citizens and the economy from the dramatic rise in fossil fuel prices." (conflicts on decade with NYC-2011 |
| When the system was expanded in the 1980s, the main concerns were socioeconomics and security of supply; environment came later | NYC-2011 | see above | p. 1: "While the socioeconomics and security of the City's heating supply were main concerns when the district heating system was expanded in the 1980's, environmental impacts became and remain a major concern" |
| District heating covers 98% of the heating demand in Copenhagen | HOFOR-WEB | see above | "Our district heating covers 98% of the heating demand in Copenhagen." |
| 98% of Copenhagen's total heating needs, about 50 million square meters (2011) | NYC-2011 | see above | p. 3: "the district heating network covers 98% of the total heating needs of Copenhagen, the equivalent to approximately 50 million square meters" |
| C40 states the system serves 98% of Copenhagen's buildings | C40-2015 | see above | "The system serves 98% of Copenhagen's buildings." (a building count, not a demand share |
| Nationally, district heating serves 64% of Danish households | DF | see above | "The Danish district heating sector provides 64 pct. of all Danish households with district heating." (nowcity.co says about 64.5%; consistent) |
| HOFOR supplies 667,000 customers in the City of Copenhagen through 1,504 km of pipe | HOFOR-AR25 | see above | PDF p. 18: "667.000 kunder"; "1.504 km rør"; "HOFOR leverer 667.000 kunder i Københavns Kommune." |
| Most heat comes from the large power plants, including Amagerværket, and from waste incineration; HOFOR also uses its own peak-load plants, heat pumps and industrial surplus heat | HOFOR-AR25 | same | PDF p. 18: "Størstedelen af varmen ... kommer fra de store kraftværker, herunder Amagerværket samt fra affaldsforbrænding. Herudover produceres varmen på egne spidslastanlæg og varmepumper samt varme fra industriel overskudsvarme." |
| Heat is distributed as hot water in a closed pipe system to customers' connection installations; network heat loss is under 10% | HOFOR-AR25 | same | PDF p. 18: "Fjernvarmen distribueres som varmt vand i et lukket rørsystem til kundernes tilslutningsanlæg"; "varmetab, som i dag er reduceret til under 10 pct." |
| Meters in all larger buildings are read remotely; remote reading for other customers to be complete at the start of 2026 | HOFOR-AR25 | same | PDF p. 18: "I alle større ejendomme fjernaflæses fjernvarmeforbruget, mens fjernaflæsning for øvrige fjernvarmekunder ... fuldt gennemført i starten af 2026." |
| HOFOR's map of heat sources includes Amagerværket, ARC (waste), heat pumps, peak plants and heat storage (varmelagre) | HOFOR-AR25 | same | PDF p. 18 graphic labels: "Amagerværket", "forbrænding", "Varme-pumpe", "Varmelagre", "El-kedel", "Geotermi", "Solvarme"; PDF p. 19 map: "ARC (ARC)", "Varmepumpe, Nordhavnen", "Varmepumpe, Sluseholmen" |
| The regional system pools CHP plants, waste incinerators and peak boilers; waste incineration supplied about 30% of regional heat demand (2011) | NYC-2011 | see above | p. 1: "connects four CHP plants, three waste incineration plants, and more than 50 peak load boiler plants with more than 20 distribution companies in one large pool-operated system"; p. 3: "Waste incineration currently supplies approximately 30% of the heat demand in the larger metropolitan Copenhagen region." |
| A 4 km tunnel under the harbor carries heat from Amagerværket to the city center | NYC-2011 | same | p. 2: "a large-scale district heating tunnel from Amagerværket under the harbor. The tunnel is 4 kilometers long" |
| District heating replaced individual heating, eliminating tens of thousands of chimneys | NYC-2011 | same | p. 1: "District heating replaces individual heating, eliminating the use of tens of thousands of chimneys." |
| The network has been adapted to different fuels and technologies over the decades | NYC-2011 | same | p. 4: "it has been adapted to different fuels and technologies following changing political priorities over the decades." |
| HOFOR owns Amagerværket; it burns only certified sustainable biomass (wood pellets and wood chips), bought from many countries | HOFOR-AR25 | see above | PDF p. 16: "HOFOR ejer Amagerværket"; "Amagerværket producerer udelukkende el og varme med certificeret bæredygtig biomasse som brændsel. Biomassen indkøbes fra en lang række lande"; "dels træpiller, dels træflis" |
| Amagerværket covers about 72% of heat demand in the City of Copenhagen | HOFOR-AR25 | same | PDF p. 16: "Amagerværket dækker ca. 72 pct. af varmebehovet ... i Københavns Kommune" (same report, PDF p. 36, says 25% of "Københavns fjernvarmebehov" |
| Block 1 (wood pellets) started 2009; Block 4 (wood chips) started 2021 by HOFOR's count | HOFOR-AR25 | same | PDF p. 16: "Blok 1, der blev sat i drift i 2009, bruger træpiller"; "Blok 4, der blev sat i drift i 2021, bruger træflis" |
| Block 4 was put into operation in 2020 by the city's count; HOFOR took over Amagerværket in 2014 | KK-SVAR26 | see above | p. 1: "Amagerværkets blok 4 anvender træflis og blev idriftsat i 2020"; p. 2: "Amagerværket først overgik til HOFORs ejerskab i 2014" |
| The coal unit ran until replaced in 2020 by BIO4 (wood chips); Ramboll credits it with cutting CO2 by one million metric tons a year and making more than 80% of the capital's district heat carbon neutral; BIO4 burns 1.2 million metric tons of wood chips a year and supplies about 25% of Copenhagen's heat demand | RAMBOLL | see above | "ran on coal until it was replaced in 2020 by a new unit, BIO4, which runs on sustainable wood chips"; "CO2 reductions of one million tonnes per year"; "has made more than 80% of the district heating supply in the Danish capital carbon neutral"; "Annually, the plant consumes 1.2 million tonnes of sustainable wood chips"; "BIO4 supplies approximately 25% of the heat demand in Copenhagen" |
| HOFOR invested DKK 5.2 billion in a new CFB unit at Amagerværket | HOFOR-WEB | see above | "We invested DKK 5.2 billion in a new CFB unit." |
| Amagerværket is Denmark's largest point source of biogenic CO2 | HOFOR-AR25 | see above | PDF p. 36: "Amagerværket, som årligt producerer 10.355 TJ varme ... er Danmarks største punktkilde til biogen CO2." |
| Certified biomass counts as zero in the city's geographic CO2 accounts | KK-SVAR26 | see above | p. 3: "certificeret biomasse har international status som vedvarende energi og CO2-neutralt brændsel, hvorfor det tæller som 0 i den geografiske CO2-opgørelse." |
| HOFOR today uses only biomass certified under schemes including FSC, PEFC and SBP | KK-SVAR26 | same | p. 2: "HOFOR oplyser desuden, at de i dag udelukkende anvender biomasse, der er dokumenteret bæredygtig gennem internationalt anerkendte certificeringsordninger, herunder FSC, PEFC og SBP." |
| 99% of the biomass HOFOR used in 2020 was imported, from countries including Estonia, Brazil, Norway, Spain and Germany; at least 83% from EU countries | ALT-2021 | see above | "99 procent af den biomasse, som hovedstadens forsyningsselskab HOFOR brugte i 2020"; "hentet fra lande som Estland, Brasilien, Norge, Spanien og Tyskland" |
| HOFOR used 169,000 metric tons of wood pellets and 640,000 metric tons of wood chips in 2020 | ALT-2021 | same | "169.000 tons træpiller, 640.000 tons træflis, og 400 tons træstammer" |
| The climate minister called biomass burning a transitional solution; HOFOR had no concrete target for cutting imports (2021) | ALT-2021 | same | Dan Jørgensen: "være en overgangsløsning"; Charlotte Søndergren: "Men vi har ikke konkrete mål for, hvor langt vi skal ned og hvornår." |
| HOFOR's district heat is 85% CO2-neutral (2025 report) | HOFOR-AR25 | see above | PDF p. 34: "Den fjernvarme, HOFOR sender ud til kunderne, er 85 pct. CO2-neutral." |
| HOFOR's group target list still reads "100% CO2-neutral energy solutions in 2025" | HOFOR-AR25 | same | PDF p. 34: "100 pct. CO2-neutrale energiløsninger i 2025" |
| District heating was 85% CO2-neutral in January 2024, largely because HOFOR phased out coal at Amagerværket | ALT-2024 | see above | "Fjernvarmen er 85 procent CO2-neutral i dag."; "Det er i høj grad lykkedes, fordi HOFOR har udfaset brugen af kul på Amagerværket" |
| The 2015 plan: over 15 years to 2025, HOFOR would make the system carbon neutral by moving from coal, oil and gas to biomass, cutting 500,000 metric tons of CO2 a year by 2025, with a 65 MW geothermal plant | C40-2015 | see above | "Over a 15-year period ending in 2025, the Greater Copenhagen Utility (HOFOR) will make the system carbon neutral by transitioning from coal, oil, and natural gas to sustainable biomass"; "500,000 tons of CO2 reduced per year by 2025"; "a 65 MW geothermal renewable energy facility" |
| Target set by Heat Plan Copenhagen: 100% renewable and waste heat in the network by 2025; 35% at the time (2011) | NYC-2011 | see above | p. 4: "the target set out for Copenhagen Energy is to obtain a 100% share of renewable energy and waste incineration heat in the DH system by 2025. The current share of renewable energy is 35%." |
| Copenhagen aimed to be the first CO2-neutral capital by 2025 | NYC-2011 | same | p. 4, Timeline: "2025 Copenhagen aims to be the first CO2 neutral capital in the world" |
| District heating emits 40% less CO2 than individual gas boilers and half that of oil boilers (Greater Copenhagen, 2011) | NYC-2011 | same | p. 3: "40% lower CO2 emissions than individual gas boilers and half the CO2 emissions of individual oil boilers" |
| Copenhagen gave up its 2025 carbon-neutral goal in August 2022 after the ARC waste plant could not get national carbon-capture funding | LOCAL-2022 | see above | "The city of Copenhagen has given up on a long-term goal of becoming carbon neutral by 2025."; "The plant is therefore unable to acquire the necessary CO2 extraction technology" |
| The city's 2021 road map already had a 430,000 metric ton shortfall; ARC announced in early August 2022 it was ineligible; the mayor suggested 2026, 2027 or 2028 | CHN-2022 | see above | "at the beginning of August 2022, the semi-public utility Amager Resource Center" ...; "it included a shortfall of 430,000 tonnes of CO₂"; "the city may still reach climate neutrality in 2026, 2027 or 2028" |
| The mayor said Copenhagen had cut CO2 emissions by 80 percent (2022) | LOCAL-2022 | see above | "Copenhagen has already slashed CO2 emissions by 80 percent." |
| The new city goal is to be climate-positive within the municipality in 2035; Klimastrategi 2035 and Klimahandleplan 2026 to 2028 adopted by the city council on September 18, 2025 | KK-SVAR26 | see above | p. 1: "Vedtagelse af Klimastrategi 2035 og Klimahandleplan 2026-2028 vedtaget i BR 18/9-25"; p. 4: "Målsætningen ... om at opnå klimapositivitet inden for Københavns Kommune i 2035" |
| Geographic emissions in Copenhagen were 0.7 million metric tons CO2e in 2024 | KK-SVAR26 | same | p. 4 table: "Geografiske udledninger (2024) ... 0,7 mio. ton CO2e" |
| The climate strategy has a sub-goal to reduce biomass use; only 49 MW of heat pumps and 30 MW of electric boilers are expected in operation by end of 2028; low-temperature district heating is expected fully rolled out in 2033 | KK-SVAR26 | same | p. 1: "delmål 1 - reducering af biomasseforbrug"; p. 3: "blot 49 MW varmepumper og 30 MW elkedler forventes i drift inden udgangen af 2028, samt at lavtemperatur fjernvarme først forventes fuldt udrullet i 2033" |
| HOFOR plans 300 MW of heat pumps, 550 MW of electric boilers and more heat storage by 2033, DKK 3 to 5 billion in all, cutting biomass use at the capital region's CHP plants 30 to 35% by 2033 against 2024 | HOFOR-AR25 | see above | PDF p. 36: "samlet kapacitet på 300 MW varmepumper"; "550 MW elkedler og flere varmelagre"; "reducere biomasseforbruget på kraftvarmeværker i hovedstadsområdet med 30-35 pct. i 2033 målt i forhold til biomasseforbruget i 2024"; "3-5 mia. kr." |
| New heat pumps: Herjedalgade (treated wastewater), 29 MW from 2027, about 13,500 households; Sundkrogsgade (seawater), 24 MW from early 2028, about 12,500 apartments | HOFOR-AR25 | same | PDF p. 4: "tilføjer 29 MW fjernvarme til fjernvarmenettet fra 2027 ... renset spildevand ... ca. 13.500 husstandes"; "24 MW fjernvarme til fjernvarmenettet fra starten af 2028 ... ca. 12.500 lejligheder" |
| The network temperature must be lowered for heat pumps; most customers will not notice, but some older Copenhagen buildings will need technical upgrades | HOFOR-AR25 | same | PDF p. 4: "For langt de fleste kunder vil de lavere temperaturer ikke kunne mærkes, men nogle ældre ejendomme i København vil få behov for tekniske opgraderinger af utidssvarende anlæg." |
| At the end of 2025 HOFOR and Elimini decided not to bid in the state carbon-capture tender, citing uncertainty about CO2 storage, a tight timeline and large guarantees; the project could remove many hundreds of thousands of metric tons of biogenic CO2 a year | HOFOR-AR25 | same | PDF p. 5: "i slutningen af året valgte HOFOR og Elimini sammen ikke at byde på puljen, da der var for stor usikkerhed om et slutlager for den indfangede CO2, for stram tidsplan samt behov for store garantier"; "mange hundrede tusind ton biogen CO2" |
| HOFOR sells district heat at cost under the non-profit (hvile-i-sig-selv) rules; price is set from the company's costs | HOFOR-AR25 | same | PDF p. 18: "Salg af fjernvarme sker til kostpris og efter hvile-i-sig-selv-bestemmelserne. Prisen på fjernvarme opgøres således på baggrund af selskabets omkostninger." |
| The non-profit principle sets which costs can enter the heat price; price must not exceed the cost of heat production; it protects customers from abuse of a natural monopoly | DF | see above | "The principle of non-profit dictates which costs can be covered in the heating price."; "the price of district heating must not exceed the cost of heat production"; "protected against possible abuse as a result of the industry's natural monopoly state" |
| Danish district heating is municipally owned or consumer-owned cooperatives | DF | same | "In addition to municipally-owned companies"; "the cooperative is owned by its own customers" |
| A national price cap on consumer heat prices took effect January 1, 2025, benchmarked against the cost of an individual heat pump; if a company is over the cap three years running, customers' obligation to connect is lifted (they still pay an exit fee); HOFOR was 23% under the cap in 2025 | HOFOR-AR25 | same | PDF p. 28: "Pr. 1. januar 2025 blev de nye prislofter på kundernes priser på fjernvarme indført"; "benchmarket op imod omkostninger til en individuel varmepumpe"; "Hvis et fjernvarmeselskab ligger over prisloftet tre år i træk, bliver tilslutningspligten ... fjernet"; "HOFOR lå i 2025 23 pct. under prisloftet." |
| The cap is based on the cost of an individual air-to-water heat pump | Ministry of Climate, Energy and Utilities, follow-up agreement to the 2022 climate agreement (read via search excerpt only) | https://kefm.dk/Media/638554354774996004/Opfølgende%20aftale%20ifm.%20klimaaftale%20om%20grøn%20strøm%20og%20varme%202022%20og%20Rigs%20revisionens%20beretning%20om%20tilsyn%20med%20aftaler%20i%20forsyningssektoren.pdf | Excerpt: "et prisloft, som vil tage afsæt i omkostningerne for en individuel luft-til-vand varmepumpe" (corroborates HOFOR-AR25) |
| District heating cost about 45% of oil heating and 56% of natural gas for a typical home (Copenhagen Energy estimate, 2009) | C40-2016 | see above | "In 2009, Copenhagen Energy ... estimated that district heating costs for a typical home were around 45% of those for oil heating and 56% of natural gas" |
| District heating cost about 50% of oil and 60% of gas for a 130 m2 home using 18 MWh a year, taxes included (2011) | NYC-2011 | see above | p. 3: "In 2011, the cost of district heating is approximately 50% of the alternative cost of oil for a 130 square meter home having an annual consumption of 18 MWh/year, including energy taxes"; "approximately 60% of the alternative cost of natural gas heating" |
| Danish district heating features include mandatory connection, a non-profit principle and relatively high average prices; future challenges include rising biomass import dependency and competition from individual heat pumps | JW-2022 | see above | Abstract (via RePEc and search excerpt): "Future challenges for the Danish district heating sector include increasing biomass import dependency, ... and competition from individual heat pumps in single-family houses." The features list (mandatory connection, non-profit principle, relatively high average prices) is from the RePEc abstract as summarized by the fetch tool, not a verbatim quote |
| The City of Copenhagen is sole shareholder of HOFOR Forsyning Holding P/S, whose annual report covers district heating | KK-ØU26 | see above | "Københavns Kommune udgør, som eneaktionær, generalforsamlingen i HOFOR Forsyning Holding P/S"; the board "vil være bestyrelse for HOFOR Fjernvarme P/S" |
| HOFOR's ownership is complex; some companies are owned jointly by several municipalities, others solely by the City of Copenhagen | HOFOR, "Organisation" | https://hofor.dk/english/organisation | "The ownership structure is complicated as some companies are jointly owned by several municipalities" |
| HOFOR's district heating arm had net revenue of DKK 3,334 million and pre-tax profit of DKK 238 million in 2025 | HOFOR-AR25 | see above | PDF p. 18 table: "Nettoomsætning 3.334"; "Årets resultat før skat 238" |
| From 2016, Copenhagen would not allow new or old oil-fired installations where district heating or gas networks exist | C40-2016 | see above | "Starting in 2016, Copenhagen will not allow new or old oil-fired installations in areas where district heating or natural gas networks are available." |
| The last steam plant closed in April 2021, four years ahead of the 2025 target; conversion began in 2009; about 100 km of pipe added; 1,300 steam installations closed; saves about 322 million kWh and DKK 200 million a year | DBDH-2021 | see above | "closed the last remaining steam power plant yesterday"; "We have added approx. 100 km of pipes"; "closed 1300 steam power plants"; "saves the city just over 322 million kilowatt-hours"; "saves Copenhageners DKK 200 million annually" |
| One third of Copenhagen's heat was distributed as steam (2011) | NYC-2011 | see above | p. 2: "One third of the total heat demand in Copenhagen is distributed as steam." |
| HOFOR invested more than DKK 500 million replacing the last section of steam network | HOFOR-WEB | see above | "We have invested more than DKK 500 million in replacing the last section of the steam-based district heating network" |
| US: IDEA's database lists 660 district energy systems; about 5.5 billion square feet of heating floorspace served in 2012; mostly colleges, hospitals, downtowns and government campuses | EIA-2018 | see above | Report p. 1: "District energy systems are more commonly found in commercial clusters of buildings such as colleges, hospitals, downtowns, healthcare, and government campuses."; "IDEA database of 660 existing district energy systems"; "In 2012, an estimated 5.5 billion square feet of heating floorspace ... were serviced by district energy." |
