Tesla is one way to reduce carbon emissions from automobiles. It is not the only way. There is also:

* Battery-electric vehicles manufactured by other companies

* Plugin hybrid-electric vehicles manufactured by other companies

* Reducing automobile usage in general

* Developing energy-efficient processes to synthesize carbon-neutral liquid fuels using carbon-neutral energy sources

* Developing new and more efficient carbon-neutral energy sources and using them to synthesize carbon-neutral liquid fuels

* Developing the technology to trap or sequester carbon emissions

* Some combination of the above