Zero energy level and economic potential of small-scale building-integrated PV with different heating systems in Nordic conditions

Janne Hirvonen, Genku Kayo, Ala Hasan, Kai Sirén

    Research output: Contribution to journalArticleScientificpeer-review

    22 Citations (Scopus)

    Abstract

    Solar electricity is growing very popular in the world, but it has some problems in matching of generation and demand both in hourly and seasonal levels. In northern latitudes the problem is especially significant, as the difference between solar availability in winter and summer is very large. Cooling needs do not increase electricity demand in summer as much as in southern locations, while there is a high demand for heating in the winter when solar power is not available. This study looks into the economics and energy matching of photovoltaic (PV) systems for single-family houses in Finland. It also introduces the concept of zero energy level of buildings (ZEL), which can be used as a policy tool for renewable energy support schemes. PV self-consumption is compared between cases with district heating (DH), heat pump (HP) and direct electric heating (EH). Because the price of buying electricity is much higher than selling it, any excess PV power after meeting appliance loads was fed to a thermal storage to be stored as heat. Analysis was done for a single building and a community of ten similar buildings. Excess solar power provided part of the space heating (SH) needs in spring and autumn and most domestic hot water (DHW) needs in summer. Self-consumption was increased by 15.70% with EH and by 20.40% with HP, when a PV system was used for space and DHW heating during summer and midseasons. Thermal storage increased energy matching, but high storage capacities did not provide a significant improvement over lower ones. Levelised cost of energy (LCOE) for PV electricity in a single building almost reached grid parity (11 c/kWh) using EH, but the generation cost for HP and DH remained higher (13 and 17 c/kWh, respectively). Investment incentives reduced the LCOE below grid prices for electrically heated systems. In the community, the economies of scale lowered LCOE, such that in many cases grid parity was reached even without incentives.
    Original languageEnglish
    Pages (from-to)255-269
    JournalApplied Energy
    Volume167
    DOIs
    Publication statusPublished - 2016
    MoE publication typeA1 Journal article-refereed

    Fingerprint

    Electron energy levels
    Electric heating
    heating
    Heating
    Economics
    electricity
    Electricity
    economics
    photovoltaic system
    energy
    solar power
    District heating
    Pumps
    summer
    cost
    Solar energy
    Costs
    investment incentive
    Hot water heating
    Space heating

    Keywords

    • Self-consumption
    • Photovoltaic system
    • Solar heating
    • Renewable energy support
    • On-site energy matching
    • Finland

    Cite this

    @article{33810f804c6a413dbf65a181016fd4db,
    title = "Zero energy level and economic potential of small-scale building-integrated PV with different heating systems in Nordic conditions",
    abstract = "Solar electricity is growing very popular in the world, but it has some problems in matching of generation and demand both in hourly and seasonal levels. In northern latitudes the problem is especially significant, as the difference between solar availability in winter and summer is very large. Cooling needs do not increase electricity demand in summer as much as in southern locations, while there is a high demand for heating in the winter when solar power is not available. This study looks into the economics and energy matching of photovoltaic (PV) systems for single-family houses in Finland. It also introduces the concept of zero energy level of buildings (ZEL), which can be used as a policy tool for renewable energy support schemes. PV self-consumption is compared between cases with district heating (DH), heat pump (HP) and direct electric heating (EH). Because the price of buying electricity is much higher than selling it, any excess PV power after meeting appliance loads was fed to a thermal storage to be stored as heat. Analysis was done for a single building and a community of ten similar buildings. Excess solar power provided part of the space heating (SH) needs in spring and autumn and most domestic hot water (DHW) needs in summer. Self-consumption was increased by 15.70{\%} with EH and by 20.40{\%} with HP, when a PV system was used for space and DHW heating during summer and midseasons. Thermal storage increased energy matching, but high storage capacities did not provide a significant improvement over lower ones. Levelised cost of energy (LCOE) for PV electricity in a single building almost reached grid parity (11 c/kWh) using EH, but the generation cost for HP and DH remained higher (13 and 17 c/kWh, respectively). Investment incentives reduced the LCOE below grid prices for electrically heated systems. In the community, the economies of scale lowered LCOE, such that in many cases grid parity was reached even without incentives.",
    keywords = "Self-consumption, Photovoltaic system, Solar heating, Renewable energy support, On-site energy matching, Finland",
    author = "Janne Hirvonen and Genku Kayo and Ala Hasan and Kai Sir{\'e}n",
    year = "2016",
    doi = "10.1016/j.apenergy.2015.12.037",
    language = "English",
    volume = "167",
    pages = "255--269",
    journal = "Applied Energy",
    issn = "0306-2619",
    publisher = "Elsevier",

    }

    Zero energy level and economic potential of small-scale building-integrated PV with different heating systems in Nordic conditions. / Hirvonen, Janne; Kayo, Genku; Hasan, Ala; Sirén, Kai.

    In: Applied Energy, Vol. 167, 2016, p. 255-269.

    Research output: Contribution to journalArticleScientificpeer-review

    TY - JOUR

    T1 - Zero energy level and economic potential of small-scale building-integrated PV with different heating systems in Nordic conditions

    AU - Hirvonen, Janne

    AU - Kayo, Genku

    AU - Hasan, Ala

    AU - Sirén, Kai

    PY - 2016

    Y1 - 2016

    N2 - Solar electricity is growing very popular in the world, but it has some problems in matching of generation and demand both in hourly and seasonal levels. In northern latitudes the problem is especially significant, as the difference between solar availability in winter and summer is very large. Cooling needs do not increase electricity demand in summer as much as in southern locations, while there is a high demand for heating in the winter when solar power is not available. This study looks into the economics and energy matching of photovoltaic (PV) systems for single-family houses in Finland. It also introduces the concept of zero energy level of buildings (ZEL), which can be used as a policy tool for renewable energy support schemes. PV self-consumption is compared between cases with district heating (DH), heat pump (HP) and direct electric heating (EH). Because the price of buying electricity is much higher than selling it, any excess PV power after meeting appliance loads was fed to a thermal storage to be stored as heat. Analysis was done for a single building and a community of ten similar buildings. Excess solar power provided part of the space heating (SH) needs in spring and autumn and most domestic hot water (DHW) needs in summer. Self-consumption was increased by 15.70% with EH and by 20.40% with HP, when a PV system was used for space and DHW heating during summer and midseasons. Thermal storage increased energy matching, but high storage capacities did not provide a significant improvement over lower ones. Levelised cost of energy (LCOE) for PV electricity in a single building almost reached grid parity (11 c/kWh) using EH, but the generation cost for HP and DH remained higher (13 and 17 c/kWh, respectively). Investment incentives reduced the LCOE below grid prices for electrically heated systems. In the community, the economies of scale lowered LCOE, such that in many cases grid parity was reached even without incentives.

    AB - Solar electricity is growing very popular in the world, but it has some problems in matching of generation and demand both in hourly and seasonal levels. In northern latitudes the problem is especially significant, as the difference between solar availability in winter and summer is very large. Cooling needs do not increase electricity demand in summer as much as in southern locations, while there is a high demand for heating in the winter when solar power is not available. This study looks into the economics and energy matching of photovoltaic (PV) systems for single-family houses in Finland. It also introduces the concept of zero energy level of buildings (ZEL), which can be used as a policy tool for renewable energy support schemes. PV self-consumption is compared between cases with district heating (DH), heat pump (HP) and direct electric heating (EH). Because the price of buying electricity is much higher than selling it, any excess PV power after meeting appliance loads was fed to a thermal storage to be stored as heat. Analysis was done for a single building and a community of ten similar buildings. Excess solar power provided part of the space heating (SH) needs in spring and autumn and most domestic hot water (DHW) needs in summer. Self-consumption was increased by 15.70% with EH and by 20.40% with HP, when a PV system was used for space and DHW heating during summer and midseasons. Thermal storage increased energy matching, but high storage capacities did not provide a significant improvement over lower ones. Levelised cost of energy (LCOE) for PV electricity in a single building almost reached grid parity (11 c/kWh) using EH, but the generation cost for HP and DH remained higher (13 and 17 c/kWh, respectively). Investment incentives reduced the LCOE below grid prices for electrically heated systems. In the community, the economies of scale lowered LCOE, such that in many cases grid parity was reached even without incentives.

    KW - Self-consumption

    KW - Photovoltaic system

    KW - Solar heating

    KW - Renewable energy support

    KW - On-site energy matching

    KW - Finland

    U2 - 10.1016/j.apenergy.2015.12.037

    DO - 10.1016/j.apenergy.2015.12.037

    M3 - Article

    VL - 167

    SP - 255

    EP - 269

    JO - Applied Energy

    JF - Applied Energy

    SN - 0306-2619

    ER -