If only there were a highly compact self correcting self replicating data storage system with 1's and 0's the size of small molecules...
In the future, if sequencing becomes extremely fast and cheap, it might make sense to discard sequencing data after analysis and leave DNA in its original format for storage. That said, if the colony of (bacteria/yeast/whatever you are maintaining your library in) that you happen to pick when you grow up a new batch to maintain the cell line happened to pick up a mutation in your gene of interest, you won't know until you sequence it again. I'm a graduate student in a small academic lab and if I want to "access my stored gene data" in the way you suggest, I need to: 1) Grow an overnight culture from my freezer stock of E. coli carrying a plasmid with my gene of interest inserted in it. 2) Isolate the plasmid DNA. 3) Take a reading on a spectrometer to determine DNA concentration. 4) Prepare a sample for sequencing at the concentration the Core Facility prefers. 5) Fill out an order form for sequencing. 6) Walk the sample over to the Core Facility. 7) Wait 1 to 3 days to get my sequence data back. I can pull up the FASTA file I have from the last time I got this gene sequenced in about 15 seconds.
There is no working algae biofuel plant.
This company seems to be making great progress on bringing the algae technology to market. They have a pilot plant in Texas, last I checked.