http://danfoss.ipapercms.dk/Drives/DSI/Casestories/UK/Michelin/RSS.ashxDanfoss Solar Inverters PagesFri, 29 Apr 2011 09:55:19 +0200http://danfoss.ipapercms.dk/Drives/DSI/Casestories/UK/Michelin/http://danfoss.ipapercms.dk/Drives/DSI/Casestories/UK/Michelin/?Page=1http://danfoss.ipapercms.dk/Drives/DSI/Casestories/UK/Michelin/?Page=1MAKING MODERN LIVING POSSIBLE Solar Inverter Solutions String inverter design enables 3 MW for Michelin in Valladolid, Spain Facing complex roofing challenges and variable shading conditions, string inverter technology along with lightweight design & efficiency help pave the upgrade path for Michelin Tires in Valladolid, Spain. In Valladolid, Spain, Michelin Tires took to the task of constructing a two-megawatt solar facility in February 2010. This endeavor, commissioned by facility owners Michelin and initiated by Cenit Solar, exceeded expectations in efficiency while meeting government regulated power limitations of two megawatts. Thus, one year later, an expansion upgrade to three megawatt output yielded a 50% increase in energy generation for Michelin and stands as one of the largest power plants in the region. Just over one year ago, Cenit Solar Proyectos e Instalaciones Energeticas, S.L. embarked on a strategy to utilise 44.000 square meters of largely unused rooftop to elevate the facility from solely an energy consumer to a solar grid energy producer. The Cenit design and installation team began by instituting an evaluation process that would best secure the optimum components capable of achieving the greatest yield, efficiency and return on investment. The challenges ahead would present significant obstacles including constructing the buildout around a complex array of rooftop chimneys. “The multi-string inverters allowed us to eliminate rows in some of the DC inputs without changing the number of modules in series”, said Project Director, Antonio Munoz. Additionally, restrictions on drilling any rooftop holes would prove to be a difficult hurdle to overcome. Cenit Engineers, in collaboration with CIDAUT (Research and Development Center in Transport & Energy) looked to develope innovative solutions which could sustain numerous modules capable of widthstanding winds up to 140 km per hour. Facility planners at Cenit were determined to transform the 300.000 square meter space to produce energy it could then sell to the public distribution network. 720 MPPT’s provide the flexibility needed for a complex string layout. www.danfoss.com/solar2011-04-29T09:55:19+02:00http://danfoss.ipapercms.dk/Drives/DSI/Casestories/UK/Michelin/?Page=2http://danfoss.ipapercms.dk/Drives/DSI/Casestories/UK/Michelin/?Page=2Benchmark testing draws definitive conclusions In an effort to substantiate initial assessments by Alternativas Energeticas y Medio Ambiente, Sociedad Limitada (AEMA, SL), PV plant owner and developer, Cenit Solar Engineers, conducted exhaustive benchmark testing, concluding that Danfoss’ TripleLynx inverters produced the most likely scenario for maximising yield while reaching efficiencies of 98%. Cenit Engineers, assessing the Michelin Tire facility rooftop, adorned with several chimneys, relied upon multiple input MPP Tracking systems to best optimise yield. String Independence & Module Variance The TripleLynx inverter’s string design played a critical role in the planning stages, allowing developers to create a layout design directly from every row of modules to each input of inverters, avoiding the costly and space consuming installation of junction boxes. This technology combined with 1000V input, 250-800V range and multiple DC inputs, created a scenario where the solar setup could carry power longer at higher levels of voltage, keeping power losses to a minimum. As roof space and system configuration proved to be significant factors in moving forward with the upgrade to three-megawatts, the multi-string concept played a vital role in providing a wide enough range of flexibility for the planning team at Cenit Solar to feel confident in the expansion. The option of installing independent strings and a varying number of modules gave Cenit a tremendous amount of flexibility and control in how they would arrange the module setup. Because Michelin is a production facility which requires steam exhaust through the numerous rooftop chimneys, the inverters controlling the modules required the sophistication and flexibility to adjust to shading and structural challenges. User-friendlyaccessibilityandsystemsmanagementdevelopedbyDanfossEngineers,”. paireddown(potential)correctivemaintenancetimesto20minuteswithverylittleaffecton overallenergyproduction.”saidCenitSolarProjectDirector,AntonioMunoz. ChallengesfacingtheMichelinTirefacilityincludedmultiplechimneysandvaryingweather conditions–overcomebyTripleLynxMPPTtechnology. “At varying points of the day, some modules will ultimately become subject to shading. This has a direct impact on our bottom line. Having 720 MPPT (Maximum Power Point Trackers – three per inverter) helps keep losses to minimum levels”, Mr. Munoz continued. The 2010 build and first-phase launch generated 3.243.150 kWh per year – an 8% higher level of production than expected. “As systems efficiencies and yields surpassed our projected numbers and the path grew clear of legal barriers (which set a two-megawatt ceiling on energy production), we felt we had all the technological pieces in place to procede with our threemegawatt build and increase output by 1.6 million kWh per year. And with the success of our existing setup, we felt comfortable keeping with and expanding on the existing hardware”, Munoz concluded. A high efficiency solution The electricity produced at the Michelin facility continues to exceed Cenit projections. The TripleLynx inverters, reaching 98% efficiency helped the Michelin Tire facility to best optimize power output most consistently throughout the day. Finally, advanced TripleLynx cooling ultimately extends the life of the inverters and helps protect the overall solar setup. As output data is accumulated in the coming months and years, the Michelin Tire facility, as a result of the efforts of the creative PV design team at Cenit Solar, could prove to be a solid model throughout Europe when constructing, managing and monitoring large-scale, rooftop multiple string inverter energy sites. Contact: JuanJoseFerrandis ProductManager DanfossSolarInverters Madrid,Spain PA.01.C1.02 ProducedbyPE-MMSC2011.042011-04-29T09:55:19+02:00