4 effect of pv module degradation and failure on system performance v3.1
1 like1,010 views
First Solar has evolved its approach to modeling and predicting operation and maintenance (O&M) costs for solar power plants. Originally, O&M costs were estimated using an Excel model with limited failure rate data and assumptions. First Solar now uses reliability block diagram modeling along with field failure data to predict component-level and system-level availability and costs more accurately. This allows optimization of system designs to maximize energy production and minimize total cost of ownership, which is increasingly important as the levelized cost of energy is the primary metric used to evaluate solar projects. First Solar aims to further improve cost predictions by working to standardize reliability data reporting across suppliers.
4 effect of pv module degradation and failure on system performance v3.1
- 2. OUTLINE: Introduction First Solar background O&M costs – History O&M costs – Present day O&M costs ‐ Future ©Copyright 2016, First Solar, Inc.
- 3. Introduction • Paul Williams, Reliability engineer, CRE, BSEET electronics • 30+ year experience in quality and reliability at high tech companies in semiconductor, computers and power generation • Jointed First Solar in 2011 ‐ Originally hired into the O&M group • Began working on upgrading and building new capabilities for O&M’s Excel based cost model • Initiated Reliability Block Diagram (RBD) modeling of components, subsystems and array level • Energy Availability prediction • Cost of ownership – Maintenance costs • Transitioned into the systems reliability engineering group 2012 • Continue to support the O&M Energy and cost models • Began working with power plant engineering to optimize systems topologies • Maximizing energy availability • Minimizing the Total Cost of Ownership (TCO) • Evangelizing and driving the concept of Levelized Cost Of Energy (LCOE) ©Copyright 2016, First Solar, Inc.
- 4. First Solar Background • One of the largest thin film solar module manufacturers and suppliers in the world • >100M modules produced • Over 10 gigawatts installed worldwide • Over 5 gigawatts under O&M Monitoring • First Solar has developed, financed, engineered, constructed, and operating some of the world’s largest PV power plants in existence. • Utility‐scale generation • Commercial & industrial • Community solar ©Copyright 2016, First Solar, Inc.
- 7. O&M Costs – History • O&M used an excel based cost model • Relied on consultants to provide failure rate information • IEEE Goldbook • MIL‐217 • Estimated the repair times based on senior management’s “experience” • Cost information provided from suppliers spare parts lists • Only outputs were labor and parts cost estimates • Could not comprehend any failure distributions other than exponential ©Copyright 2016, First Solar, Inc.
- 8. O&M Costs – Present Day • BOS manufacturers do not use consistent methods to report predicted failure rate estimates. Information is typically MTBF based. • Using Reliability Block Diagram modeling of Components, Subsystems and Array level • Energy availability prediction • Cost of ownership – Maintenance Costs • Getting suppliers to provide failure data is challenging • Using failure distribution data based on our own field experience • Using Accelerated Life Test (ALT) data for FS developed products • Working with power plant engineering to optimize systems topologies • Maximizing energy availability • Minimizing the TCO • Levelized Cost Of Energy (LCOE) starting to appear in Marketing and Sales literature. ©Copyright 2016, First Solar, Inc.
- 12. Field Data ‐ DC Health Analysis – Failure Breakdown Note: There are NO power degradation failures Results from a large >100MW power plant during a regular DC health sweep Recognition that Module Reliability (degradation) is not all there is to building a solar plant for optimized costs. ©Copyright 2016, First Solar, Inc.
- 13. O&M Costs ‐ Future • While important, module degradation is not all there is to building a solar plant for optimized costs. BOS components play a major role as well. • LCOE and Total Cost of Ownership (TCO) becomes the driving quality metrics on which power plants are evaluated • FS Initiating an IEC work item proposal to standardize cost modeling inputs for improved prediction accuracy • Standard defines a complete list of deliverables for equipment suppliers to provide in order to be able to predict and trend the cost of ownership and LCOE models. Based on failure mode and distribution parameters rather than MTBF estimates. ©Copyright 2016, First Solar, Inc.
- 14. LCOE LCOE is the lifecycle cost for investment in an electricity generation power plant. Utility companies and financial institutions value projects on the basis of the lifecycle cost, generally through a measure known as Levelized Cost of Electricity (LCOE) Development $ Construction $ O&M Costs $ Profit $ Taxes $ Etc. (cash flow) $ = LCOE ($/kWh) Understanding how LCOE is impacted by changes in the system allows First Solar to optimize plant designs (and System Solutions) that reduce LCOE most effectively • Energy yield increase has the highest single impact on LCOE • $/watt is not the driving metric for investment in utility scale PV projects and PPA’s ($/kWh) = Net energy to be sold over the life of the investment kWh ©Copyright 2016, First Solar, Inc.
- 15. First Solar AC Power Block Configurable PV Power Generation Unit for developing fully integrated utility‐scale power plants with the lowest LCOE • First Solar System and Services • First Solar Energy Prediction Model • Energy Performance Guarantee ©Copyright 2016, First Solar, Inc.