Environmental Aspects of Photovoltaic Solar Power The New Zealand Context EEA Conference 2015 Luke Schwartfeger and Allan Miller
Purpose and Content Purpose of study: To provide some clarity of the environmental benefits and detriments of PV from the overall New Zealand perspective Content Background Life cycle stages and corresponding environmental impacts PV Solar Power in New Zealand 3
Background Found that PV panels are the most important component when looking at a PV system s environmental impact Generation Description Technology Type Top Cell Efficiency (Achieved in 2014) Best Industrial Panel Efficiency (Achieved in 2012) Market Share (2013) Mature technology, 1 st mass produced for at least 20 years c-si Mono 25.0% c-si Multi 20.8% 20.5% Approximately 90% Recently entered 2 nd large scale production CdTe 21.5% 12.1% CIS/CIGS 21.7% 14.5% Approximately 10% Crystalline Silicon (c-si), Cadmium Telluride (CdTe), Copper Indium Gallium Selenide (CIGS) 4
Global Annual PV Production by Technology Fraunhofer Institute for Solar Energy Systems, Photovoltaics Report 24-10-2014 Data: from 2000 to 2010: Navigant; from 2011: IHS (Mono-/Multi- proportion estimated). Graph: PSE AG 2014 5
Life Cycle General Overview Life Cycle Analysis is a method of quantifying the environmental impacts of a product or system by looking through its life ( cradle-to-grave ) Not conducted in this study, however concept and other studies were used For this study: Life cycle stages focused on were manufacturing, operation and endof-life Environmental impacts covered were climate change, acidification and toxicity 6
Life Cycle Stage - Manufacturing Manufacturing process: c-si: Purification of silicon ore (2 stages), casting of ingots, wafer cutting, formation of the panel Thin Film: Deposition of materials on to a glass pane Toxicity risk for manufacturing staff CdTe involves cadmium, which is carcinogenic and affects lung, liver and kidney health c-si panels manufacturing process involves hydrochloric acid, trichlorosilane and tetrachlorosilane, which are acidic or react with water to form acidic substances 7
Life Cycle Stage - Manufacturing Climate Change and Acidification: Not all panels are made equal The combustion of fossil fuels results in the emissions of greenhouse gases (CO 2, CH 4, etc.) and acidification gases (SO 2, NO X ) The major manufacturing location matters because of their high fossil fuel based electricity generation E.g. China in 2012 generated 77% of its electricity from fossil fuels and it is a dominant producer of PV panel across all manufacturing stages Technology types have varying energy intensities Energy usage of manufacturing as a percentage of mono-crystalline panels Mono-crystalline Multi-crystalline CIGS CdTe 100% 58.6% 40% 22.9% 8
Offset Class and Technology Type Elec. Mix Offset Gas Offset PV Solar Power in New Zealand CIGS CdTe c-si (Multi) c-si (Mono) GHG Emission Payback Period European Manufactured Based on a life cycle analysis where the panels were manufactured in Europe and China and installed in Southern Europe CIGS CdTe c-si (Multi) c-si (Mono) Chinese Manufactured The results were altered to be more representative of New Zealand 0 2 4 6 8 10 12 14 16 18 20 Year 9
Life Cycle Stage - Operation PV generation is emissions-free, reduces the load and/or exports it to the electricity grid However, the geographical dimension of the environmental impacts is highlighted if we look at the manufacturing location and the installation location Climate Change: Global Acidification: Regional, Local Toxicity: Local 10
Life Cycle Stage - Operation The GHG electricity generation mix emission factor is used to evaluate the offset emissions of PV; this is not appropriate for grids with a high renewable generation proportion. To determine how PV offsets GHG emission, a simple way is to examine from a high level how the generated energy interacts with the grid: PV is negative load Geothermal, Coal is constant during sunlight hours Wind is unaffected Either gas or hydro is offset Offsetting hydro conserves a minor amount of water in the reservoir which is likely to offset gas in the future (More detail on this will be covered soon) New Zealand s electricity emission factor was 171 g CO 2 -e/kwh and for gas exclusively it was 430 g CO 2 -e/kwh (2013) 11
Life Cycle Stage End-of-Life Two options: Send it to the landfill or recycle it Policy on PV Recycling: The European Union s Waste Electrical and Electronic Equipment directive places the responsibility on the PV industry to manage the disposal and recycling of the panels Implementation Example: Risk of cadmium leeching if in a landfill. First Solar, a manufacturer of CdTe panels, has a recycling program attached to the sale of their panels Question for New Zealand: How will PV panels be dealt with here? 12
PV Solar Power in New Zealand GHG Emissions Target By 2020, net emissions at 95% of the level in 1990 By 2050, net emissions at 50% of the level in 1990 Renewable Energy Target 90% of the energy produced in 2025 is to be from renewable sources (hydro inflows considered) 13
MW Installed Gg CO 2 -e PV Solar Power in New Zealand 20 18 16 14 12 10 8 6 4 2 0 Installed Capacity and Avoided Emissions to date of PV 2012 2013 2014 2015 Year 14 12 10 8 6 4 2 0 Avoided Emissions from PV: 5.7 Gg CO 2 -e (gas offset, 2014) MW Installed Avoided Emissions of Electricity Mix (Gg) Avoided Emissions of Gas (Gg) 14
Pg CO 2 -e (Petagrams ) PV Solar Power in New Zealand Emissions history and future targets 90 80 70 60 50 40 30 20 10 0 1985 1990 1995 2000 2005 2010 2015 2020 2025 2030 2035 2040 2045 2050 2055 Year Gross Emissions of New Zealand (Pg) Net Emissions of New Zealand (Pg) Electricity Generation Emissions (Pg) 2020 Target 2050 Target Year of setting 2020 Target Avoided Emissions from PV: 5.7 Gg CO 2 -e (gas offset, 2014) Electricity Grid Emissions: 5476 Gg CO 2 -e (2014) Only focusing on eliminating all the emissions from the electricity grid will not make us reach our targets PV s potential is limited 15
Renewable Gneeration % GWh PV Solar Power in New Zealand 100% 95% 90% 85% 80% 75% 70% 65% Renewable generation percentage, consumption and target 42000 40000 38000 36000 34000 32000 30000 28000 26000 60% 24000 1985 1990 1995 2000 2005 2010 2015 2020 2025 2030 Year Year of setting 2025 Target 2025 Target Renewable Generation % Consumption The increase in geothermal generation and the decrease in coal generation has lead to the increase in % renewables With the options of wind and geothermal available, it is difficult to say what PV s contribution will be Median capacity factor for PV in New Zealand is approximately 15% 16
Concluding Summary PV panels are not made equal Consideration of the geographical dimension of the environmental impacts PV s end of life scenario in New Zealand still needs to be answered For New Zealand, PV will predominantly offset gas generation PV has a positive benefit to New Zealand, both for our GHG emission targets and 90% renewable goal. However, it is minor. 17