ATWELL ISLAND
OperatingSolar power plant
- Capacity
- 20 MW
- Primary fuel
- Solar
- County
- Tulare County
- Operator
- SPS ATWELL ISLAND LLC
- Status
- Operating
- Commissioned
- 2013
- EIA plant ID
- 58366
- Coordinates
- 35.8950, -119.5108
ATWELL ISLAND, a 20 MW Solar power plant in Tulare County, California. Operated by SPS ATWELL ISLAND LLC, commissioned 2013.
Weather peril exposure
ATWELL ISLAND is a 20 MW solar power plant in Tulare County, CA, operated by SPS ATWELL ISLAND LLC, commissioned in 2013. Tulare County carries low modeled catastrophe exposure in the FEMA National Risk Index, scoring 1.5 of 5 at the 14th national percentile. Wildfire is the leading peril, rated Relatively High by FEMA at the 97th percentile.
Tulare County hazard ratings
| Peril | FEMA rating | National percentile | Peril score | Share of modeled loss | Events per year |
|---|---|---|---|---|---|
| Wildfire | Relatively High | 97th | 4.9 of 5 | 60% | <0.01 |
| Heat wave | Relatively High | 95th | 4.8 of 5 | <1% | 5.4 |
| Earthquake | Relatively Moderate | 91st | 4.7 of 5 | 8% | 0.06 |
| Riverine flooding | Relatively High | 90th | 4.6 of 5 | 30% | 3.0 |
| Tornado | Relatively Low | 9th | 1.4 of 5 | 1% | 0.30 |
| Lightning | Relatively High | 8th | 1.3 of 5 | <1% | 15.7 |
| Winter weather | Very Low | 3rd | 1.1 of 5 | <1% | 13.2 |
| Strong wind | Relatively Low | 3rd | 1.1 of 5 | <1% | 0.04 |
| Hail | Relatively Moderate | 2nd | 1.1 of 5 | 1% | 0.13 |
Perils not assessed in Tulare County
These perils carry no usable National Risk Index figure for this county, so they are excluded from the scoring rather than scored zero. A zero would claim the peril was assessed and found benign.
| Peril | Why it is not scored |
|---|---|
| Hurricane | FEMA rating is "Not Applicable" for this county |
| Coastal flooding | FEMA rating is "Not Applicable" for this county |
| Ice storm | FEMA rating is "Not Applicable" for this county |
Hail exposure and deductible structure
Hail scores 1.1 of 5, which sits in the 1% to 2% percentage deductible range carriers are quoting for that exposure. Named windstorm and severe convective wind score 1.4 of 5, indicating a 1% to 1% wind deductible. Ranges, not single figures. The final structure is set by the carrier.
Percentage hail deductible range: 1% to 2% of insured value. Wind deductible range: 1% to 1%. These are the structures commonly seen at this exposure, not an offer and not a rate.
Modeled annual loss for a 20 MW solar array
At an assumed replacement value of $0.90 per watt, or $18.0M insured, the modeled expected annual loss for a fixed tilt ground mount array in Tulare County is $4,528 a year, $226 per MW, 0.03% of insured value.
Heat is modeled as a production risk rather than a property loss: 2.9% of annual yield in this county.
Insurability signal: Standard. Wildfire carries 60% of modeled loss.
Model hail, wind and flood exposure for Tulare County in the weather risk calculator
Ratings are the FEMA National Risk Index county hazard ratings; the peril score is a Bywatts transform of the FEMA national percentile, and the modeled loss applies the Bywatts solar vulnerability layer. Full data sources and the solar vulnerability methodology are in the weather risk calculator.
Modeled estimate for screening and negotiation. Built from FEMA National Risk Index county hazard data and a solar vulnerability layer documented above. Not a quote, a binder, or actuarial advice, and not a substitute for a carrier's own model. Hazard data: FEMA National Risk Index December 2025, synced 2026-07-24. Resolution is county level, not site level. The solar vulnerability layer that turns FEMA building loss into modeled solar loss was derived by Bywatts and revised on physical reasoning. It has not been reviewed by a practising underwriter.