CalStar Paver performance versus clay pavers and concrete pavers (true paver 8” x 4” at 60 mm bed depth for comparison):

Paver Type Holland CalStar Paver Clay Paver Concrete Paver
Embodied energy 1,000 BTUs 6,800 BTUs 1,500 BTUs
CO2 0.1 lbs 1.1 lbs 0.8 lbs
Recycled material 40% less than 7% Not typical
Dimensional consistency Extremely Consistent Varies (based on firing) Very consistent

 

Source: The Construction Specifier
Second Source: Brick Industry Association Tech Notes