Building Integrated Photovoltaics BIPVs

1
Building Integrated Photo-voltaics (BIPVs)

• Solar Energy Applications
• EnvS 116
• Asim Zia
• Department of Environmental Studies
• San Jose State University

2
Overview

• Life Cycle Assessment Methodology for comparing
  PV systems
• Material Input comparison for four different BIPV
  systems
• Variables for Life Cycle Impact Assessment
• Factors for Global Warming Potential (GWP) and
  CED Indicator Calculation
• Energy/CO2 Pay Back Time
• Contribution analysis for GWP and CED indicator
  of PV module production
• Summary of the main results by Battisti and
  Corrado 2005
• Cost and Cumulative Power of PV systems in
  Netherlands
• Some BIPV examples and its future

3
Life Cycle Assessment Methodology (Battisti and
Corrado 2005)

• The LCA methodology allows to assess the
  potential environmental impacts of a product or
  service during its whole life cycle (from the
  cradle to the grave)
• A LCA study is divided into the following steps
• 1. Goal and scope definition.
• 2. Life cycle inventory.
• 3. Life cycle impact assessment.
• 4. Interpretation of results.

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Data requirements for Life Cycle Inventory Phase
of LCA (Battisti and Corrado 2005)
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System boundaries for LCA of MC-Si PVs (Battisti
and Corrado 2005)
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Material Input comparison for four different BIPV
systems (Battisti and Corrado 2005)
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Characteristics of MC-Si module (Battisti and
Corrado 2005)
8
Variables for Life Cycle Impact Assessment
(Battisti and Corrado 2005)

• To process the collected data to make the life
  cycle impact assessment, two environmental
  indicators were used
• global warming potential (GWP, expressed in kg
  CO2eq), resulting from the sum of each greenhouse
  gas emission (CO2, CH4, NO2, etc.) multiplied by
  a suitable weight factor
• Cumulative energy demand (CED, expressed in MJ
  LHV, low heating value) which measures the
  primary energy needed for the whole life cycle.
  The weight factors for CED are the LHV of the
  fuels.

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Factors for Global Warming Potential (GWP)
Indicator Calculation (Battisti and Corrado 2005)
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Factors for Cumulative Energy Demand (CED)
Indicator Calculation (Battisti and Corrado 2005)
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Energy/CO2 Pay Back Time (Battisti and Corrado
2005)

• In this paper two additional parameters are used
  energy pay back time (EPBT) and CO2eq PBT.
• These parameters compare the cumulative energy
  (or the CO2 equivalent emissions) consumed over
• the whole life cycle with the cumulative energy
  (or the CO2 equivalent emissions) saved during
• operation. This approach allows to evaluate the
  real zero emission operating period and to
  compare it
• to the expected system lifespan.

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CED contributions for 1kWp PV reference system
(Battisti and Corrado 2005)
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Contribution analysis for CED indicator of PV
module production (Battisti and Corrado 2005)
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Contribution analysis for GWP indicator of PV
module production (Battisti and Corrado 2005)
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Pay Back Time values (Battisti and Corrado 2005)

• The values of PBTs are obtained by an
  environmental costbenefit analysis.
• Environmental PBTs were calculated both for CO2eq
  emissions and for cumulative energy, in order to
  estimate the time period needed for the benefits
  obtained in the operational phase to equal the
  impacts related to the whole life cycle of the
  analyzed systems.
• The calculated EPBT is 3.3 years, while CO2eq PBT
  is 4.1 years For the reference case, i.e.
  advanced retrofitted flat PV panels. Compare
  this with life time warranty of 25 to 30 years!

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PBT for different BIPV systems (Battisti and
Corrado 2005)
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Summary of the main results (Battisti and Corrado
2005)
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Conclusions (Battisti and Corrado 2005)

• Considering that the expected lifespan for PV
  systems is 1530 years, it is remarkable that all
  the analyzed configurations (even the reference
  cases) are characterized by environmental PBT one
  order of magnitude lower than their expected
  life. This is due to the significant benefits
  obtained by replacing conventional energy
  sources.
• The analysis has shown that energy and
  environmental performances of PV systems become
  more interesting as the system design is more
  integrated with the whole building design, and as
  the module is more exploited as a dual-output
  device. In particular, heat recovery for DHW
  production reduces environmental PBT of more than
  50. The increased demand for materials by the
  HRU is more than compensated by an increased
  energy output of PV modules.

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Cost and Cumulative Power of PV systems in
Netherlands (Schoen 2001)
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PV Vision 2020 in Netherlands (Schoen 2001)
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Some BIPV examples (Schoen 2001)
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Some BIPV examples (Schoen 2001)
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Some BIPV examples (Schoen 2001)
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Some BIPV examples (Schoen 2001)
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Some BIPV examples (Schoen 2001)
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Some BIPV examples (Schoen 2001)
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Planned versus Actual PV in Netherlands (Schoen
2001)
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BIPV Operational experience in Netherlands
(Schoen 2001)
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BIPV future (Schoen 2001)
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BIPV future (Schoen 2001)