By Andreas Wabbes, solar engineer and software product owner, PVComplete
The solar industry, like many other market segments since 2020, is facing several challenges that prevent it from scaling at the levels needed to meet climate agreement objectives.
Expectations for solar market scaling are being hampered by varying equipment costs, labor shortages and uncertainty related to performance, transmission upgrades and the availability of land. These challenges combined with the schedules expected by corporate and public off-takers to hit their climate goals make the current PV development environment very challenging.
If we are to realize the promise and global necessity of solar at mass scale, solar developers need tools to tackle these scarcity and uncertainty barriers.
Tools that reduce soft costs and free up engineering resources by automating, optimizing and streamlining early-stage development tasks for large numbers of projects can make a world of difference for a solar developer, especially when faced with highly competitive projects that might end up in a long interconnection queue with low chances of being built at all.
At the same time, though speed and soft cost reductions are critically important, PV designers still need the flexibility to model plants on increasingly challenging terrain and adapt to local requirements on a project-to-project basis.
Advanced multi-disciplinary solar software that can automate early design and optimization steps where possible, without constraining design engineering, is a powerful advantage when scaling is hindered by scarcity or uncertainty.
Land and transmission capacity
The more solar projects we build, the scarcer land and transmission capacity becomes — especially flat land with suitable soil conditions and high solar resources close to transmission lines with available capacity.
PV developers from California to the Netherlands and other areas with rapid solar PV market expansion often only gain access to the grid after considerable delays (and in some cases fail to gain access at all), in part because any expansion of the grid usually takes significantly longer than solar construction. In the US, more than 600 GW of solar PV sits in interconnection queues as wait times continue to grow and completion rates decline.
Revised regulations and interconnection reforms are urgently needed, but the issue remains that in order for a developer to make an informed decision based on uncertain information, all scenarios have to be preliminarily designed, optimized and modeled. Doing so with limited engineering resources and rising cost and time pressure requires advanced solar software that can transform a largely iterative manual process into an integrated digital process. Advances in computational technology now allow us to automatically handle terrain and component constraints to assess different mounting options, run thousands of parametric sweeps comparing various design options of DC:AC ratio, ground coverage ratio, azimuth and skew to maximize preliminary project economics and generate designs that can be seamlessly integrated in CAD software for more detailed topographical analysis, final engineering and documentation in a matter of minutes.
Having greater software-based insights into where to build and how to design projects on less-than-ideal terrain can help reduce project development risk and uncertainty.
For example, with rapid design engineering iteration and modeling tools, solar design software can help developers evaluate whether the energy yield and within-the-fence project economics realized by building a solar plant far from a transmission line with ample free capacity on a flat rectangular piece of land with high solar resource but an expensive interconnection is more or less economically viable than building a PV plant on fragmented or variable terrain — such as parcels that hug farmers’ fields, follow the contours of hills, conform to the boundaries of cloverleaf highways or circumvent wetlands, waterways and other precious natural resources — that is right next to a transmission line with limited capacity.
For the project represented in Figure A, a developer chose to focus development resources on this 25-MWAC project close to an available grid interconnection point on hilly terrain rather than expanding grid infrastructure on a parcel with more ideal terrain and solar conditions. Despite a 3% reduction in specific yield (kWh/kWp), an integrated analysis of terrain, topography, yield, project and interconnection costs showed that this project resulted in a lower optimal LCoE (see Figure B) with a higher completion probability. Using advanced solar software this analysis and optimization was completed in a couple of hours, whereas previous processes required days or even weeks of iterations.
You can see how advanced solar software allows us to make informed decisions and propose more projects at the same time, leading to a higher chance of success at a lower cost.
Changing cost structures and supply chain woes
Where in the past, PV projects were characterized by a module-dominated cost structure and fixed or predictable tariffs, things have changed drastically in recent years. Module costs have dropped significantly faster than balance of system, installation and other costs, to the extent that in some regions the latter have become the dominant cost drivers in utility-scale PV projects. As shown in Figure C, this trend is expected to continue for fixed-tilt utility-scale PV Systems (Source BNEF) . This changing cost structure has led to denser and more oversized (high DC/AC ratio) PV projects and makes it difficult for PV designers to continue to rely on general specific-yield heuristics to define the project optimal design vector.
Furthermore, continuing pandemic-related supply chain woes and the lingering effects of uncertainty about U.S. tariffs have delayed the deployment of gigawatts of capacity. As a result developers need flexibility to use components that are available at the time of construction and rapidly adjust designs to these components specs and constraints.
Once again advanced solar software that can quickly run through entire design vectors on a project-to-project basis is needed to give PV designers and developers the insight and flexibility needed to adapt their designs to altering markets and local regulatory conditions. It also allows to keep projects on track, even when equipment has to change, sometimes several times before a site is constructed.
Shift to multi-disciplinary PV design and analysis
As many industries before it, the solar industry has reached a maturity and complexity where traditional engineering practices need to adapt to continue scaling it to the levels required to reach net-zero carbon.
The process of developing a utility-scale PV plant normally requires the expertise of several disciplinary teams – each with a specific performance-related goal. GIS teams look for suitable terrains closest to grid infrastructure, purchase teams search for lowest-cost quality equipment, performance teams optimize the yield within heuristic constraints, civil and electrical teams design a cost-driven civil and electrical layout, and finance teams evaluate project economics. In the traditional approach, each team incorporates its insights and recommendations in a sequential and iterative manner until a workable design is achieved.
Advanced solar software is ushering in a new era of multi-disciplinary design optimization (MDO), where all relevant disciplines and inputs are incorporated into the development process simultaneously. As solar projects become more complex, software facilitates information sharing and allows multi-disciplinary teams to leverage a shared platform as a “single source of truth”. The approach ensures each step of the development process is seamlessly informed by the analysis that has already been performed, making all teams more efficient and effective in their roles as they are empowered to understand the influence of their specific design action on the final design goal. Integrated, advanced tool sets and sophisticated modeling tools allow teams to work toward a common goal in a multi-disciplinary, streamlined and flexible manner.
Overcoming scarcity and uncertainty
The solar industry is facing the very real threat that fewer projects will see completion due to scarcity and uncertainty. Though many factors will continue to influence the solar industry’s capacity to scale, advanced solar software’s ability to reduce soft costs, optimize engineering resources, manage complexity and enable greater project design flexibility empowers PV developers’ with powerful tools to combat scarcity and uncertainty, improve optimization and economics, and bring more projects to successful completion.
Andreas Wabbes is a solar engineer and software product owner at solar design software company PVComplete. With a degree in Electrical Power Engineering from Ghent University, he has extensive expertise in PV design optimization products.