ENERGY SITING — DATA BRIEFING

What weather data decides where each energy source goes

A simple breakdown for energy planners and policy teams: for every major generation type — solar, wind, hydro, nuclear, geothermal, biomass and wave/tidal — what climate and resource data you actually need to decide where to build, and what you can ignore. Each technology is sensitive to a narrow set of variables; knowing what doesn't matter makes screening much faster.

The four layers of every siting decision

Resource layer — is the fuel actually there? (sun, wind, water, heat, biomass, waves) — the weather/geology layer below.
Engineering layer — can you build it? Terrain, soil, depth, seismic, constructability.
System layer — can you get the power out? Transmission proximity, MLF, congestion, curtailment risk.
Social/regulatory layer — will it get approved? Land tenure, native title, environmental overlays, community sentiment.

Solar PV

Energy hitting the panel after losses. The fuel is sunlight, the killers are heat, dust and hail.

What matters

Global Horizontal Irradiance (GHI) — annual kWh/m²/yr, 10–20 yr lookback
Direct Normal Irradiance (DNI) — critical for concentrated solar thermal
Cloud cover climatology
Air temperature (panels lose 0.3–0.45% output per °C above 25°C)
Soiling / dust deposition rate
Hail climatology + cyclone wind zone
Slope, aspect, available land

What doesn't matter

Rain (actually helps — washes panels)
Humidity
Local wind speed (mild positive only, cools panels)
Time of day in itself (already in irradiance)

What a good site looks like

Excellent: > 2,200 kWh/m²/yr GHI — Pilbara, far western NSW, NT. PV capacity factor 27–32% with single-axis tracker.

Wind

Wind power scales with the cube of speed. Get the hub-height wind regime right and you've covered ~95% of the resource question.

What matters

Hub-height wind speed (130–170 m, not the BoM 10 m mast)
Wind direction (wind rose)
Wind shear (α exponent — how speed grows with height)
Turbulence intensity (TI)
Air density (cold dense air = ~3–5% more power)
Extreme wind 50-yr return (sets IEC turbine class)
Terrain complexity, cyclone zone

What doesn't matter

Rain (tiny aerodynamic effect)
Sunshine / cloud cover
Humidity
Day vs night (many sites blow harder at night)
Local rainfall (matters for construction access, not resource)

What a good site looks like

Excellent: hub-height mean 8–9 m/s — VIC western district, Mid-North SA, New England NSW. Onshore CF 38–45%. Offshore (Gippsland declared zone) modelled 45–55%.

Hydro

Run-of-river and reservoir hydro are rainfall-driven. Pumped storage is a head + grid arbitrage problem, not a rainfall problem.

What matters

Catchment rainfall — 100+ yr record ideally
Streamflow at the site (gauges, 30+ yr)
Snowpack / snowmelt timing (alpine NSW/VIC)
Evapotranspiration over the catchment
Head (vertical drop, m)
Climate-uplifted runoff projections (Millennium Drought sequence)
For pumped storage: head, basin geology, head-to-distance ratio

What doesn't matter

Daily sunshine / wind (only via evapotranspiration totals)
Daily temperature (monthly aggregates matter)
Daily rainfall (catchment-aggregated weeks/months matter)

What a good site looks like

Tropical RoR can hit 50–70% CF. Snowy-style reservoir 40–60%. Pumped storage isn't CF-driven — value is MWh stored × $/MWh peak-trough spread.

Nuclear

Not weather-driven for output. Sited by cooling water, seismic and flood — over a 60–80 year asset life, so future climate matters more than history.

What matters

Continuous cooling water reliability (m³/s)
Cooling water temperature (under future climate)
Seismic Peak Ground Acceleration at 10⁻⁴ / 10⁻⁵ annual exceedance
Probable Maximum Flood + storm surge + sea-level rise
Population inside 5/10/16 km Emergency Planning Zone
Switchyard + transmission capacity (the ex-coal site advantage)
Long-term climate projections to 2100

What doesn't matter

Sunshine / cloud / rain (except as flood input)
Wind (except for plume dispersion safety case)
Daily weather generally

What a good site looks like

Best case: existing coal switchyard + reliable ocean or large-river cooling + low population EPZ + low seismicity. Inland Murray–Darling fails on cooling under future climate. CF 85–93% for modern LWR.

Geothermal

The resource is underground heat, not weather. Australia's prospects are Hot Sedimentary Aquifer + Enhanced Geothermal Systems — not yet commercial.

What matters

Thermal gradient (°C/km — Cooper Basin hot spots > 50 °C/km)
Temperature at target depth (> 200°C for power)
Heat flow (mW/m²)
Rock thermal conductivity
Permeability + in-situ stress regime
Depth to crystalline basement
Induced-seismicity risk + distance to grid

What doesn't matter

All surface weather (small ambient effect on air-cooled cycle only)
Rainfall, sunshine, wind

What a good site looks like

Where viable, CF 80–95% (baseload). Australian high-grade conventional resource is essentially absent; HSA/EGS proven hot at Cooper Basin but not yet commercial.

Biomass

The fuel is grown over years, then hauled. Project economics are dominated by delivered feedstock cost per GJ at the plant gate.

What matters

Multi-year rainfall + growing-degree-days
Standing biomass yield (t/ha/yr)
Haul distance economics (rarely > 80 km by road)
Co-location with existing infrastructure (sugar mills, sawmills)
Drought sequence resilience
Competing uses (pulp, mulch, soil cover)
EPA emissions limits (NOx, PM2.5)

What doesn't matter

Daily weather on operation day (plant runs regardless)
Daily sunshine, wind, temperature

What a good site looks like

Sugar bagasse co-gen (in-season 80–95% CF, ~50% annual). Wood-residue plants 70–90%. Energy-from-waste 80–90%. Biomass is dispatchable — that's why it stays in plans.

Wave + Tidal

Wave power scales with Hs² × Te. Tidal stream scales with current³. Australian best sites: southern WA/SA, Tasmania, Kimberley.

What matters

Significant wave height (Hs) + energy period (Te) — 30+ yr hindcast
Wave direction and spectrum
Tidal current speed (need > 1.5 m/s spring mean)
Tidal range × basin area (for tidal range schemes)
Water depth + seabed type
Extreme metocean (Hs100)
Distance to cable landfall

What doesn't matter

Sunshine, local rain
Local wind (waves come from distant fetch)
Tides aren't 'weather' — they're astronomically predictable

What a good site looks like

Wave (Southern Ocean swell): CF 25–45% top sites. Tidal stream: 20–40% locked to lunar cycle. Tidal output is predictable but not dispatchable.

The one factor that matters for every source: transmission

Resource quality without grid access is worthless. A 28% capacity-factor solar site with an MLF of 1.05 beats a 30% site with 0.80 every time. The shortest screening question for any candidate site is:

Distance to the nearest network connection point of adequate voltage — line losses scale roughly 5–8% per 500 km in the NEM.
AEMO Marginal Loss Factor (MLF) at that point — West Murray solar saw MLFs collapse from 1.0 to 0.7, killing several projects.
Hosting capacity + curtailment risk — congested zones can curtail 15–30% of output.
HVAC vs HVDC — overhead AC works to ~600–800 km; submarine cable goes HVDC beyond ~80 km (why Marinus Link is HVDC).

Source briefs: Research/energy-siting/ (10 numbered notes) · Pipeline plan: Design/Energy-Siting-Data-Pipeline.mdAustralian data sources referenced: Bureau of Meteorology, AEMO ISP + MLF tables, Geoscience Australia, AREMI (ARENA), CSIRO Climate Change in Australia, ANU 100% Renewable Energy Group PSH atlas, CAWCR Wave Hindcast.