Independent research · June 2025
In San Diego, the electric car is cleaner than the bus.
I measured four Rancho Bernardo trips door to door — cost, time and carbon — and surveyed 16 neighbours about why they drive. Two of the three findings went against what I expected.
The bus is four minutes long
Route 1 is the trip I make most: home to Rancho Bernardo High School, 3.5 miles. By car it takes 9-12 min. By transit it takes 46 minutes, and Route 945 runs the whole way with no transfers.
That framing hides the problem. Almost all of that time is spent on foot.
This reframes what the study is even about. Transit here is not slow because the buses are slow — the bus is four minutes. It is slow because the network is out of reach from either end. That is a first- and last-mile problem, and it is fixable without touching the bus route at all.
Parking decides the cost
I expected transit to be cheaper everywhere. It is not. On short trips ending somewhere with free parking — school, the gym — driving costs about a dollar and transit costs $5.00. Paying a flat fare to save a dollar of fuel makes no sense, and residents know it.
The moment a destination charges for parking, the arithmetic inverts. Downtown, the $20 parking fee swamps the fuel difference: driving costs $29.88 round trip against $5.00 by bus.
The surprising one: the bus is not the cleanest option
A gas car emits 0.7 lbs of CO2 per mile. A transit bus, per passenger, emits 0.18. An electric car charged on San Diego’s grid emits 0.13 — about a quarter less than the bus.
This is a local result, not a general one. SDG&E’s grid carries a high renewable share, so the electricity going into the car is unusually clean. Run the same comparison somewhere coal-heavy and the bus wins comfortably.
What 16 neighbours said
I asked 16 people around Rancho Bernardo what stops them using transit. The answers were not about money.
Convenience led at 7 of 16, and when people explained what they meant it was almost always distance to a stop: a 0.9-mile walk at each end, a stop too far for someone with bad knees, a route that doesn’t work with a stroller. Cost was named once.
What would actually help
All three findings point the same way. The bus itself is fine. Reaching it is the problem, and the fixes are about closing that gap rather than adding service.
- 01
Increase Route 945 frequency at peak
Reduce wait times from 30 minutes to 15 during the hours students and workers actually travel. Time was the second most cited barrier.
- 02
A first- and last-mile neighbourhood shuttle
The single highest-value change. A small connector feeding Route 945 attacks the 42 minutes of walking directly — the 4-minute bus ride is not the problem.
- 03
Employer transit partnerships
Several respondents named free workplace parking as the reason driving wins. Large Rancho Bernardo employers subsidising passes would change that calculation without any new infrastructure.
Method
Four routes measured door to door in June 2025 using Google Maps and MTS schedules. Costs are round trip and include parking where charged; emissions are one way. Prices and factors are listed below and every figure on this page is computed from them.
Survey responses were collected in person from 16 Rancho Bernardo residents. It is a convenience sample, not a representative one, and the numbers should be read as indicative rather than statistically robust.
- Gas price
- $5.49/gal · Costco San Diego, Jun 2025
- Gas car
- 28 MPG · typical sedan or SUV
- EV efficiency
- 3.5 mi/kWh · EPA average
- Electricity
- $0.45/kWh · SDG&E estimate
- Transit fare
- $2.50/ride · MTS single ride
- Downtown parking
- $20/day · estimated $15–$35