Floating Solar Site Selection: GIS & MCDA

GIS mapping for floating solar: suitability analysis via MCDA & AHP

GIS for Renewable Energy: Mapping the Path to Floating Solar Power in the Philippines  

The push for renewable energy is reshaping the global landscape and the geospatial community plays a crucial role in this transition. Photovoltaics are a popular solution and a more specific method being studied is installing these on floating platforms on lakes and reservoirs. Floating Solar Photovoltaics or FSPVs as they are often referred to, present a viable alternative, particularly for countries with limited land for large scale plants. This exploration looks at a real-world example and a research effort done within an island nation that examines suitability mapping and goes beyond traditional cost-benefit studies by focusing also on environmental impact and community factors using spatial tools.

Floating Solar? Addressing Land Constraints  

Traditional, land-based photovoltaic installations, despite their proven benefits can require significant areas. This land consumption can cause some issues when land use overlaps between critical natural habitats or agricultural resources. As such there is the obvious desire to avoid that, if at all possible. For locations with significant access to water, using floating platforms on large water bodies is an opportunity to bypass some of these land issues. Aside from needing a fraction of land usage compared to regular plants these installations could additionally show improved power generation because the bodies of water can provide cooling effects. This also offers a means to offset evaporation. So in simple terms the opportunity for higher electrical yield while saving some water as well as freeing up land area. But obviously, not all water bodies are automatically suitable, hence the focus on spatial data analytics for accurate evaluation.

Multicriteria Decision Analysis (MCDA) with Geospatial Precision

The core methodology used here goes by the name Multicriteria Decision Analysis. It is a crucial process for systematically weighing various parameters to choose the best possible option among many choices. This analysis goes beyond typical project design phases, incorporating a wide range of critical variables such as proximity to power transmission networks, natural reserves or road networks. Other important factors to examine are the areas with tourist attractions or fishing industry areas all being balanced into an aggregate assessment using advanced analytical geospatial methods. This thoroughness of approach illustrates that a true sustainable development needs more considerations beyond just simple techno-economic projections alone. By carefully reviewing environmental impacts and stakeholder feedback within this geographic evaluation system it allows us to design strategies that fit in naturally with human activity and ecological frameworks of a given location.

Analytical Hierarchy Process (AHP): The Framework for Weighing Factors

So how can we put a system together to manage all these spatial relationships and variable attributes? We use the Analytical Hierarchy Process, which simplifies decision making through a hierarchal system of ranking various competing criteria. Essentially using the opinions of experts and community figures this method evaluates factors against one another in order to create a set of relative weight factors or significance on our spatial area under assessment. Each key metric will be compared against all other criteria using interviews of individuals who work within areas related to solar power projects, from environmental managers and industry consultants through to local governance figures, before the matrix can have assigned weighting for analysis. These pairwise rankings by each stakeholder are collated, tested for mathematical validity, aggregated into a cohesive format and subsequently analysed to quantify those weights or priority scores before this is applied to geographic spatial data. This step highlights how valuable insights gained from various real world perspectives is essential in guiding informed geospatial decisions. This ensures the project is properly situated on the proper ground, so to speak. This also avoids those problems of theoretical assumptions being out of line with reality.

GIS: Visualizing Suitability Across the Philippine Archipelago

With spatial criteria and data firmly defined and quantified and with AHP determined parameters as the framework, the Geographic Information System now moves to the center stage. GIS transforms abstract ideas of spatial suitability into maps that are easy to see and understand. It becomes immediately visually apparent which sites may potentially hold the most opportunities or possible dangers. Various types of geospatial datasets are used, some may include but not be limited to; power infrastructure lines, regions with natural protected reserves, the distribution networks of roads and data showing current and potential population or locations with active tourism industry spots. Then this data will be rendered as different layers using spatial tools available in modern geospatial systems to clearly understand each single facet independently or as part of an combined assessment for any possible sites within the area of study. This comprehensive strategy gives planners or stake holders a way to directly view the landscape’s complexities before undertaking costly on ground survey or project implementation tasks and additionally shows areas requiring further attention on potential projects.

Specific Spatial Datasets and Techniques  

Various geospatial technologies are used in generating location suitability maps. Some of the crucial approaches used are described as follows: To calculate the impact of human presence areas data sets from OCHA population raster datasets of municipality sizes and the analysis is further resampled so as to obtain approximate population densities near target sites for the projects under evaluation. When the time comes to evaluating areas based upon a proximity requirement for natural conservation, we can bring data such as Philippine Marine Protected Area databases and areas within OpenStreetMap into our system to help generate a map showing protected regions.

Proximity to infrastructure also provides critical insight. Data regarding electrical infrastructure transmission networks derived from sources such as OpenStreetMap. These dataset when mapped out visually and spatial buffers are implemented around such zones with further scoring based on proximity calculations that help visualize possible target area selections that also takes cost factors into account and ensures power generation sources are situated as efficiently as possible for project success.

Another spatial area that can assist a project is when infrastructure roads is incorporated with analysis by leveraging datasets provided by Philippine government departments. By looking at a proximity map which measures distances and locations of transportation networks near the different target sites, you have now gained critical data points to see and weigh logistical challenges as a result for a project implementation that considers supply chain logistics of each option under review. Fishing areas using government data on fish port sites are given weighted priority, where those closer to active marine activity areas may have implications when using this in overall analysis, therefore all target area analysis must be completed with spatial analytical methods prior to any site selection process to be in line with our conservation approach. Similar consideration must also go for Tourism, where areas of major touristic value using the geospatial data via OpenStreetMap will undergo proximity-based assessments that allow consideration on impacts within recreational areas. By gathering detailed information sets and analysis across the entire scope of each relevant topic we are better prepared for long term environmentally sound spatial planning initiatives that ensure all areas and impacts will receive the correct level of due process with proper consideration and scrutiny using the tools offered via GIS.

Mapping and Tiering of FSPV Suitable Sites

Now having established how our data points will be evaluated, lets have a closer examination at our results. GIS allows the consolidation of the individual geospatial metric data and creates a single final score by considering each parameter in terms of the assigned weights from the AHP framework. By combining the various data, there can then be visual interpretation of highly ranked water areas as identified through suitability evaluation using spatial datasets. These bodies are then separated based on scores above 90 showing highly rated spots to possible spots with below 70 as deemed less suited areas using parameters mentioned previously and with their accompanying geographic data mapped using our spatial system. These final score maps display which areas in the Philippine archipelago are most advantageous with respect to geospatial data. Some of the locations being highlighted may include places with relatively low marine area protected areas or good road and transmission lines coupled with better or poorer ratings with fishing and or tourist locations in mind as previously discussed, thereby painting an holistic view for each specific target project spot that goes well beyond just basic economic data sets or technical limitations alone.

Balancing Conservation, Livelihood and Clean Energy

Now with these final suitability data and ranking maps laid out for detailed assessment. What becomes critically clear to us are complex interplay that is associated with development efforts such as what the real world will require. For example some lakes, such as Lake Tikub and Lake Caluangan both rank highly by numerical data with excellent infrastructure or distance parameters but at the same time will have significant involvement by local fishermen in the form of daily fishing as their source of life and income as such any proposal to place industrial plants may well put people’s living or the sensitive aquatic systems that are already experiencing great environmental distress. Dams appear to score relatively well too and while less prone to this same livelihood conflict there still needs to be in depth survey prior to starting of any work in any of the proposed site locations as this also helps the environment long term sustainability. All such scenarios showcase our requirement to move forward with responsible actions. Environmental protection for fragile water habitats along with communities and socioeconomic factors must remain the highest level of importance within sustainable design initiatives.

Specific Examples in the Philippines

Based upon the multi-faceted geospatial analytical process. Sites like the Bulacan and Benguet regions and associated large river dam basins may represent those options that have good ratings spatially in relation to criteria that are weighted according to survey results as the least impactful and highly suited. Dams like Ambuklao, Binga or San Roque and large water holding regions appear in analysis as potentially viable options after they clear biodiversity and further assessments which is of crucial consideration prior to real implementation steps are taken in the field for industrialization efforts such as this type. There also appeared to be highly desirable but complicated target zones such as those found in Laguna de Bay or in San Pablo city’s cluster lakes region where environmental studies as well as current conditions and economic or recreational considerations such as illegal activity must be resolved prior to projects, before the location can ever have implementation of infrastructure. The spatial technology allows the easy identification of areas and also clearly lays out potential issues beforehand rather than discovering these problems when time has already been invested or mistakes already been made that have long term consequences on natural spaces.

Final Thoughts

The geospatial profession now finds itself playing a critical role in designing systems to assess, test and determine potential impacts of proposed projects by delivering precise data and planning strategies which help manage resource constraints. Spatial analysis goes beyond numbers, encompassing socioeconomic facets for balanced, sustainable initiatives in a rapidly evolving era for large development plans across the globe and this all starts within local communities using tools such as GIS. The implementation of a sound geospatial based plan which is further paired with data surveys gives developers a better long term planning methodology that ensures long lasting successful renewable energy strategies for the future that ensures benefits that do not come at the expense of nature. This methodology will allow spatial science field to keep being as critical partner for all human progress and its ever increasing demands to make sustainable pathways forward into the future.