---
_id: '24550'
abstract:
- lang: eng
  text: "Efficiencies and energy yields of microinverters available on the market
    during 2014‒2021 have been \r\nmeasured, compared, and ranked. Conversion efficiencies
    as a function of load have been measured indoors with high \r\naccuracy and ranked
    according to Euro- and CEC weightings. Energy yields have been measured outdoors
    via \r\nidentical and calibrated crystalline silicon PV modules of 215 Wp (until
    2020) and 360 Wp (starting 2021). Inverters \r\nwith two inputs have been fed
    by two of those modules. DC input, AC power output and energy yield of each micro\x02inverter
    have been recorded by individual calibrated electricity meters. CEC and EU efficiency
    rankings have been \r\ncomputed and compared. To assess the influence of PV module
    size, two extremes have been investigated: A rather \r\nsmall module with 215
    Wp - as it has been used 10 years ago, and a brand-new module (2021) offering
    360 Wp. Both \r\ntypes of modules contain 60 solar cells in series connection.
    Appling the low-power modules, the challenge for the \r\ndifferent micro-inverters
    has been during weak-light conditions, using the high-power modules, some inverters
    \r\ntemporarily reach their power limits and yield is reduced. A method using
    a reference configuration of inverter & \r\nmodule and a linear equation y = ax
    + b resulting in the actual yield, any module & inverter configuration can be
    \r\ncharacterized by just the coefficients a and b."
author:
- first_name: Stefan
  full_name: Krauter, Stefan
  id: '28836'
  last_name: Krauter
  orcid: 0000-0002-3594-260X
- first_name: Jörg
  full_name: Bendfeld, Jörg
  id: '16148'
  last_name: Bendfeld
citation:
  ama: 'Krauter S, Bendfeld J. Module-Inverters (Microinverters): Influence of Module
    Size on Conversion Efficiencies and Energy Yields. In: <i>Proceedings of the 38th
    European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC 2021)</i>.
    ; 2021:659-663. doi:<a href="https://doi.org/10.4229/EUPVSEC20212021-4CO.3.4">10.4229/EUPVSEC20212021-4CO.3.4</a>'
  apa: 'Krauter, S., &#38; Bendfeld, J. (2021). Module-Inverters (Microinverters):
    Influence of Module Size on Conversion Efficiencies and Energy Yields. <i>Proceedings
    of the 38th European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC
    2021)</i>, 659–663. <a href="https://doi.org/10.4229/EUPVSEC20212021-4CO.3.4">https://doi.org/10.4229/EUPVSEC20212021-4CO.3.4</a>'
  bibtex: '@inproceedings{Krauter_Bendfeld_2021, title={Module-Inverters (Microinverters):
    Influence of Module Size on Conversion Efficiencies and Energy Yields}, DOI={<a
    href="https://doi.org/10.4229/EUPVSEC20212021-4CO.3.4">10.4229/EUPVSEC20212021-4CO.3.4</a>},
    booktitle={Proceedings of the 38th European Photovoltaic Solar Energy Conference
    and Exhibition (EU PVSEC 2021)}, author={Krauter, Stefan and Bendfeld, Jörg},
    year={2021}, pages={659–663} }'
  chicago: 'Krauter, Stefan, and Jörg Bendfeld. “Module-Inverters (Microinverters):
    Influence of Module Size on Conversion Efficiencies and Energy Yields.” In <i>Proceedings
    of the 38th European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC
    2021)</i>, 659–63, 2021. <a href="https://doi.org/10.4229/EUPVSEC20212021-4CO.3.4">https://doi.org/10.4229/EUPVSEC20212021-4CO.3.4</a>.'
  ieee: 'S. Krauter and J. Bendfeld, “Module-Inverters (Microinverters): Influence
    of Module Size on Conversion Efficiencies and Energy Yields,” in <i>Proceedings
    of the 38th European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC
    2021)</i>, 2021, pp. 659–663, doi: <a href="https://doi.org/10.4229/EUPVSEC20212021-4CO.3.4">10.4229/EUPVSEC20212021-4CO.3.4</a>.'
  mla: 'Krauter, Stefan, and Jörg Bendfeld. “Module-Inverters (Microinverters): Influence
    of Module Size on Conversion Efficiencies and Energy Yields.” <i>Proceedings of
    the 38th European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC
    2021)</i>, 2021, pp. 659–63, doi:<a href="https://doi.org/10.4229/EUPVSEC20212021-4CO.3.4">10.4229/EUPVSEC20212021-4CO.3.4</a>.'
  short: 'S. Krauter, J. Bendfeld, in: Proceedings of the 38th European Photovoltaic
    Solar Energy Conference and Exhibition (EU PVSEC 2021), 2021, pp. 659–663.'
conference:
  end_date: 2021-09-10
  name: 38th European Photovoltaic Solar Energy Conference and Exhibition (EUPVSEC
    2021)
  start_date: 2021-09-06
date_created: 2021-09-16T10:17:11Z
date_updated: 2022-01-06T13:22:03Z
ddc:
- '620'
department:
- _id: '53'
doi: 10.4229/EUPVSEC20212021-4CO.3.4
file:
- access_level: closed
  content_type: application/pdf
  creator: krauter
  date_created: 2022-01-06T13:20:31Z
  date_updated: 2022-01-06T13:20:31Z
  file_id: '29175'
  file_name: Krauter Bendfeld - Module size Microinverters - EUPVSEC 2021.pdf
  file_size: 5413518
  relation: main_file
  success: 1
file_date_updated: 2022-01-06T13:20:31Z
has_accepted_license: '1'
keyword:
- AC-modules
- Microinverter
- Power Conditioning
- Efficiency
- Yield
- PV module size
- saturation
- performance
language:
- iso: eng
page: 659 - 663
publication: Proceedings of the 38th European Photovoltaic Solar Energy Conference
  and Exhibition (EU PVSEC 2021)
publication_identifier:
  isbn:
  - 3-936338-78-7
publication_status: published
quality_controlled: '1'
status: public
title: 'Module-Inverters (Microinverters): Influence of Module Size on Conversion
  Efficiencies and Energy Yields'
type: conference
user_id: '28836'
year: '2021'
...
---
_id: '18387'
abstract:
- lang: eng
  text: " During comparative measurements of different PV microinverters, two yield
    issues came up that could \r\nnot be explored via conventional efficiency measurements,
    but do have a significant impact on electrical energy \r\nyield: First category
    of issues are either sluggish or nervously acting maximum–power–point–tracking
    devices, which \r\nlead to reduced energy yields. The other category of issues
    is thermal: As a first explanation for observed reduced \r\nenergy yields, it
    has been assumed that the conversion efficiency degrades at higher operating temperatures.
    This \r\nmatter has been investigated in this article: A change in conversion
    efficiency could not be observed for elevated \r\noperation temperatures up to
    50°C, despite high-precision and repeated measurements. But it was found that
    some \r\ninverters temporarily interrupted (or entirely stopped) operation after
    long periods of running at high temperatures. \r\nAlso, a reduction in potential
    maximum power output has been detected for those inverters. Summarizing: With
    a \r\nhigh degree of certainty it can be stated that those reported yield losses
    have been caused by the temporary shutdowns \r\nand power limitations of the inverters."
author:
- first_name: Stefan
  full_name: Krauter, Stefan
  id: '28836'
  last_name: Krauter
  orcid: 0000-0002-3594-260X
- first_name: Jörg
  full_name: Bendfeld, Jörg
  id: '16148'
  last_name: Bendfeld
citation:
  ama: 'Krauter S, Bendfeld J. Elevated Temperatures Affecting Efficiency, Overall
    Performance and Energy Yield of PV Microinverters. In: <i>Proceedings of the EU
    PVSEC 2020 </i>. ; 2020:1179-1180. doi:<a href="https://doi.org/10.4229/EUPVSEC20202020-4AV.3.6">10.4229/EUPVSEC20202020-4AV.3.6</a>'
  apa: Krauter, S., &#38; Bendfeld, J. (2020). Elevated Temperatures Affecting Efficiency,
    Overall Performance and Energy Yield of PV Microinverters. <i>Proceedings of the
    EU PVSEC 2020 </i>, 1179–1180. <a href="https://doi.org/10.4229/EUPVSEC20202020-4AV.3.6">https://doi.org/10.4229/EUPVSEC20202020-4AV.3.6</a>
  bibtex: '@inproceedings{Krauter_Bendfeld_2020, title={Elevated Temperatures Affecting
    Efficiency, Overall Performance and Energy Yield of PV Microinverters}, DOI={<a
    href="https://doi.org/10.4229/EUPVSEC20202020-4AV.3.6">10.4229/EUPVSEC20202020-4AV.3.6</a>},
    booktitle={Proceedings of the EU PVSEC 2020 }, author={Krauter, Stefan and Bendfeld,
    Jörg}, year={2020}, pages={1179–1180} }'
  chicago: Krauter, Stefan, and Jörg Bendfeld. “Elevated Temperatures Affecting Efficiency,
    Overall Performance and Energy Yield of PV Microinverters.” In <i>Proceedings
    of the EU PVSEC 2020 </i>, 1179–80, 2020. <a href="https://doi.org/10.4229/EUPVSEC20202020-4AV.3.6">https://doi.org/10.4229/EUPVSEC20202020-4AV.3.6</a>.
  ieee: 'S. Krauter and J. Bendfeld, “Elevated Temperatures Affecting Efficiency,
    Overall Performance and Energy Yield of PV Microinverters,” in <i>Proceedings
    of the EU PVSEC 2020 </i>, online, 2020, pp. 1179–1180, doi: <a href="https://doi.org/10.4229/EUPVSEC20202020-4AV.3.6">10.4229/EUPVSEC20202020-4AV.3.6</a>.'
  mla: Krauter, Stefan, and Jörg Bendfeld. “Elevated Temperatures Affecting Efficiency,
    Overall Performance and Energy Yield of PV Microinverters.” <i>Proceedings of
    the EU PVSEC 2020 </i>, 2020, pp. 1179–80, doi:<a href="https://doi.org/10.4229/EUPVSEC20202020-4AV.3.6">10.4229/EUPVSEC20202020-4AV.3.6</a>.
  short: 'S. Krauter, J. Bendfeld, in: Proceedings of the EU PVSEC 2020 , 2020, pp.
    1179–1180.'
conference:
  end_date: 2020-09-11
  location: online
  name: EU PVSEC 2020, 37th EU Photovoltaik Solar Energy Conference
  start_date: 2020-09-07
date_created: 2020-08-27T06:26:25Z
date_updated: 2022-01-06T12:32:47Z
ddc:
- '620'
department:
- _id: '53'
doi: 10.4229/EUPVSEC20202020-4AV.3.6
file:
- access_level: closed
  content_type: application/pdf
  creator: krauter
  date_created: 2022-01-06T12:27:02Z
  date_updated: 2022-01-06T12:27:02Z
  file_id: '29171'
  file_name: Krauter Bendfeld - Microinverters at elevated temperatures EUPVSEC 2020.pdf
  file_size: 599660
  relation: main_file
  success: 1
file_date_updated: 2022-01-06T12:27:02Z
has_accepted_license: '1'
jel:
- Q42
keyword:
- AC-modules
- Microinverter
- Power Conditioning
- Thermal Performance
- Ventilation
- Stability
- Efficiency
- Yield
language:
- iso: eng
page: 1179 - 1180
publication: 'Proceedings of the EU PVSEC 2020 '
publication_identifier:
  issn:
  - 3-936338-73-6
publication_status: published
quality_controlled: '1'
status: public
title: Elevated Temperatures Affecting Efficiency, Overall Performance and Energy
  Yield of PV Microinverters
type: conference
user_id: '28836'
year: '2020'
...