Artikkelit

Hajian, H., Ahmed, K. & Kurnitski, J. (2022). Dynamic heating control measured and simulated effects on power reduction, energy and indoor air temperature in an old apartment building with district heating.

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Julkaisun nimiDynamic heating control measured and simulated effects on power reduction, energy and indoor air temperature in an old apartment building with district heating.
KirjoittajatHatef Hajian, Kaiser Ahmed, Jarek Kurnitski
JulkaisijaEnergy and Buildings
ISBN/DOIhttps://doi.org/10.14214/sf.10609 
Julkaisupäivä13.05.2022
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Abstract

This study investigated the effects of the dynamic heating control on power reduction and indoor air temperature in a typical Finnish block of apartments built in 1981. The building operated in 2018 with conventional and in 2020 with dynamic heating control. The onsite measured data was collected from both periods. Measured data enabled calibrating the whole building simulation models with an accuracy better than 10%. A new dynamic heating curve control algorithm was developed so that outdoor air compensated supply temperature was reduced during high use of Domestic Hot Water (DHW) by applying DHW compensation differential. If the indoor air temperature in any apartment dropped below the limit, supply temperature uplift was applied. The dynamic heating control resulted in 8.9% space heating and 13.7% total heating power reduction while had practically no effect on energy use. On the contrary, dynamic heating control slightly increased indoor temperature fluctuations, but both control systems resulted in a similar value of hours below the setpoint temperature of 21 °C. The results demonstrate that heating power reduction without compromising indoor air temperature is possible with applied supply temperature drop during DHW peaks and preheating afterwards.

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Mikola, A., Hamburg, A., Kuusk, K., Kalamees, T., Voll, H., Kurnitski, J. (2021). The impact of the technical requirements of the renovation grant on the ventilation and indoor air quality in apartment buildings.

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Julkaisun nimiThe impact of the technical requirements of the renovation grant on the ventilation and indoor air quality in apartment buildings.
KirjoittajatAlo Mikola, Anti Hamburg, Kalle Kuusk, Targo Kalamees, Hendrik Voll, Jarek Kurnitski
JulkaisijaBuilding and environment
ISBN/DOIhttps://doi.org/10.1016/j.buildenv.2021.108698
Julkaisupäivä15.2.2022
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Abstract

In this study, the impact of ventilation requirements set in the conditions of a renovation grant was analysed with field measurements. Effects of renovation measures applied in two grant periods on the air change rate (ACR) and indoor air quality (IAQ) of apartments were examined. CO2 levels and airflow rates were measured in 21 buildings during the first renovation grant period and in 15 buildings in the second grant period. During the first grant period, the average ACR studied apartments was as low as 0.17 h1, and in the second grant period ACR had improved to 0.57 h1, complying with requirements. Room-based ventilation requirements as well as heat recovery and preheating of intake air, mandatory airflow rate and sound pressure level measurement protocols, and third party inspection of design documentation assured adequate ventilation and IAQ in the second grant period. Centralized mechanical supply and exhaust ventilation with heat recovery resulted in best performance but an alternative system with exhaust heat pump and ventilation radiators may also be recommended. We concluded, that the installation of proper ventilation system is a key issue in renovation. The results of the study are a valuable input in designing technical conditions of the renovation grant.

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Räihä, J., Ruokamo, E. (2021). Determinants of supplementary heating system choices and adoption consideration in Finland

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Julkaisun nimiDeterminants of supplementary heating system choices and adoption consideration in Finland
KirjoittajatJouni Räihä, Enni Ruokamo
JulkaisijaEnergy and buildings
ISBN/DOIhttps://doi.org/10.1016/j.enbuild.2021.111366
Julkaisupäivä15.11.2021
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Tiivistelmä

Omakotitaloasujat voivat parantaa lämmityksen energiatehokkuutta lisäämällä tukilämmitysjärjestelmän päälämmitysjärjestelmän rinnalle. Päälämmitysjärjestelmävalintaa on tutkittu laajasti, mutta pelkästään tukilämmitysjärjestelmävalintaan keskittyvää tutkimusta on tehty vain vähän. Tämä tutkimus keskittyy tukilämmitysjärjestelmävalintaan ja hankinnan harkintaan. Tutkimus pohjautuu uuden omakotitalon rakentaneille tehtyyn kyselyyn. Hankintapäätösten analysoinnissa käytetään diskreetin valinnan malleja, ja tuloksia tulkitaan innovaatioiden diffuusioteorian kautta. Tutkittavat tukilämmitysjärjestelmät ovat aurinkopaneeli, aurinkokeräin, ilmalämpöpumppu sekä vesitakka. Tulosten mukaan suomalaiset kodinomistajat ovat vastaanottavaisia tukilämmityksen suhteen. Valintapäätökseen vaikuttavia tekijöitä ovat muun muassa ikä, koulutus, ympäristöasenteet sekä informaatiokanavat.

Abstract

Detached house owners can improve energy efficiency in heating by adding a supplementary heating system alongside the primary mode. Whereas research on primary heating mode adoption is wide, studies focusing solely on the determinants of supplementary heating system adoption is limited. This study examines the determinants of supplementary heating system adoption and consideration in Finland with a survey data collected from a sample of newly built detached house owners. We employ discrete choice modeling to investigate the homeowners’ supplementary heating system choices and interpret the results vis-à-vis the diffusion of innovations literature. The supplementary heating systems under study are solar panel, solar thermal heater, air-source heat pump and water-circulating fireplace. Overall, the findings indicate that homeowners are generally receptive to supplementary heating in Finland. The analyses show that several factors such as age, education, primary heating mode, heating system attributes, location, environmental attitudes and information channels impact the supplementary heating system adoption decision.

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