

Kari Lappalainen
Research topics
Photovoltaic power systems, energy storage systems, renewable energy, wind power, grid integration, electric vehicle charging
Latest publications
Identification of photovoltaic module ageing from symmetrically and asymmetrically cut current–voltage curves
Kalliojärvi, H. & Lappalainen, K., Mar 2026, In: Solar Energy Materials and Solar Cells. 296, 15 p., 114081 .Research output: Contribution to journal › Article › Scientific › peer-review
Dependence of Photovoltaic Module Performance Indicators on Operating Temperature and Irradiance
Kalliojärvi, H. & Lappalainen, K., 2025, 42nd European Photovoltaic Solar Energy Conference and Exhibition. EU PVSEC, 7 p. (Proceedings (EU PVSEC)).Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › Scientific › peer-review
Effects of the Operating Point of Photovoltaic Strings on Sizing of DC- and AC-Connected Energy Storage Systems for Power Smoothing
Lappalainen, K., 2025, In: Advanced Energy and Sustainability Research. 6, 10, 12 p., 2400199.Research output: Contribution to journal › Article › Scientific › peer-review
Estimating Photovoltaic Power Ramp Rates Using Single Point Irradiance Measurement
Talvi, M., Kleissl, J. & Lappalainen, K., 2025, 42nd European Photovoltaic Solar Energy Conference and Exhibition. EU PVSEC, 7 p. (Proceedings (EU PVSEC)).Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › Scientific › peer-review
Influence of the temperature on the intrinsic parameters of thin-film photovoltaic modules
Piliougine, M., Garcia-Marrero, L. E., Lappalainen, K. & Spagnuolo, G., 15 Feb 2025, In: Renewable Energy. 240, 20 p., 122068 .Research output: Contribution to journal › Article › Scientific › peer-review
Methods for online identification of photovoltaic module ageing by series resistance from measured current–voltage curves
Kalliojärvi, H. & Lappalainen, K., Jun 2025, In: Energy Reports. 13, p. 1558-1570Research output: Contribution to journal › Article › Scientific › peer-review
Photovoltaic Hosting Capacity in Nordic Distribution Grids
Aaltonen, L. & Lappalainen, K., 2025, 42nd European Photovoltaic Solar Energy Conference and Exhibition. EU PVSEC, 5 p. (Proceedings (EU PVSEC)).Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › Scientific › peer-review
Photovoltaic Modules Single-Diode Model Parametric Identification by Means of Implicit and Explicit Approaches
Lappalainen, K., Piliougine, M. & Spagnuolo, G., 2025, ELECTRIMACS 2024 - Selected Papers. Belenguer, E. & Beltran, H. (eds.). Springer, p. 601-614 14 p. (Lecture Notes in Electrical Engineering; vol. 1275).Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › Scientific › peer-review
Sizing of energy storage systems for connection power reduction and power smoothing of electric vehicle charging plazas
Lappalainen, K. & Kleissl, J., Nov 2025, In: International Journal of Electrical Power and Energy Systems. 172, 9 p., 111347.Research output: Contribution to journal › Article › Scientific › peer-review
Dependence of Series Resistance on Ideality Factor and Shunt Resistance in Online Photovoltaic Module Parametric Identification
Kalliojärvi, H. & Lappalainen, K., 2024, 41st European Photovoltaic Solar Energy Conference and Exhibition. EU PVSEC, 6 p. (Proceedings (EU PVSEC)).Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › Scientific › peer-review