Zelamene/renewable-site-screening

Dockerized PostGIS demo screening candidate solar/wind sites against grid proximity and protected land, tagged with real South African municipal boundaries (MDB shapefile). # Renewable-energy site screening A small PostGIS project that runs a first-pass spatial screen for candidate solar and wind sites in South Africa — checking grid proximity and protected-land conflicts, then tagging each site with its real municipality. > Built to reinforce PostGIS / spatial-SQL fundamentals — a focused learning exercise, not a production system. See Data and limitations. ## What it does Renewable siting needs two early checks: is there a nearby grid connection, and is the land clear of protected areas? This project runs that screen against South African data — candidate sites, substations, and exclusion zones — and outputs a `PASS / REJECT / REVIEW` verdict per site, each tagged with its real municipality (loaded from an official shapefile). ## What it covers | Step | Concept | Query | |---|---|---| | 0 | Typed geometry + GiST indexes | `geometry(Point/Polygon, 4326)` | | 1 | Distance | `ST_DWithin` on `geography` — substations within 30 km | | 2 | Nearest-neighbour join | `LATERAL` + ` ` KNN operator | | 3 | Containment | `ST_Contains` — sites inside exclusion zones | | 4 | Projection vs. geography | same distance in degrees vs. `geography` vs. UTM 34S | | 5 | Composite verdict | `PASS / REJECT / REVIEW` per site | ## Run it Copy the env template and set your own password: ```bash cp .env.example .env ``` Then: ```bash docker compose up -d ./run.sh ``` Seeds the demo data, loads the real Municipal Demarcation Board boundary shapefile, and prints each site with its municipality and verdict. `docker compose down` to tear down — there's no persistent volume, so `run.sh` re-seeds clean every run. ## Sample output ``` site | tech | municipality | verdict -----------------+-------+---------------+------------------------------- De Aar Wind | wind | Emthanjeni | PASS - screenable Augrabies Solar | solar | Kai !Garib | REJECT - protected land Prieska Solar | solar | Siyathemba | REVIEW - no grid within 30 km …