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

21 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

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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",
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}

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 -