FPGA always consume more power then its ASIC counter part
FPGA are generally used for small volume runs or for prototyping as such are very flexable in what they can achieve. i.e. they can be reconfigured for different functions. I know FPGA can be clocked at slow speed to improve power consumation, but for true power efficiency you need to look at ASICs.
ASIC are purely customised product and as such can be created as power efficient as possible. But invariable take longer to create and more expensive for low volume runs.
FPGA vs ASIC as usually, it’s a trade off between cost,speed and power.
If you sure your going to make high volume products, then go with ASIC. If not then look to use FPGA intially and then migrate to an ASIC if demand warrant it.