I retrieved your book from Amazon and I see you emphasize food calories from vegetables in your photosynthetic efficiency calculation. My emphasis, for nearly 2 decades now, has been on protein due to the trophic losses in the food chain and the growing demand for meat from Asian populations that are rapidly entering the market for meat. Its true that cultured meat, as you emphasize in your book, will have lower trophic losses than whole animal culture but the amino acids will still need to come from somewhere. Photobioreactors are at least an order of magnitude more efficient in use of insolation than soybeans. If they are floating photobioreactors protected from high seastates by a surrounding atoll, it is going to be hard to beat them for economy, even given the fact that they are only about 6% efficient in converting sunlight to biomass and only about half of that is in the form of amino acids. Floating PBRs are little more than two layers of greenhouse film with delivery plumbing for nutrients and extraction of growth medium for harvest. It will be interesting to see if an LED system can pay for itself faster than can the extra polyfilm that may be required by going for maximum sun-exposed surface area. I suspect you'll run into limits on LED intensity due to biological limits of algae.
As for the non-protein food calories, you may be correct that enclosed LED-lit food factories may dominate. However, I suspect folks would enjoy an environment filled with growing vegetables they can pick at will and many will opt for that as their decor. On Thu, Jun 12, 2014 at 1:48 PM, James Bowery <[email protected]> wrote: > There are multiple layers of confusion in our communication, Jed. To > clarify a few things: > > > - 5 mill <https://en.wikipedia.org/wiki/Mill_(currency)> is 0.005 USD, > not 0.005 cents. I am assuming that all energy, except that destined for > human food consumption, is from cold fusion electricity at 0.005USD/kWh = > 0.5cents/kWh -- a lower bound on the cost per kWh established by the > capital cost of the cold fusion energy generator being on the order of > $200/kW installed. Are you projecting $2/kW installed or even lower? If > so, it doesn't really change my argument that much since the food > consumption energy still has to go through photosynthesis which means you > still have photobioreactors. > - Agricultural feedstocks are not for energy unless you mean food > calories. If you mean food calories are "annoying and expensive to > harvest" you didn't explain why people will throw away food in the form of > aquaponic outputs of fresh fruits, vegetables and an array of seafood > including not only algae grazers such as tilapia and sockeye salmon, but > predator fish such as bluefin tuna and invertebrates such as lobster, > shrimp and clams. I did purchase your book and read it but I don't recall > anything that would substitute for demand for these end products from > agriculture or bypass the necessary foodchain/nutrient cycles in the > aquaponics systems. The book is not immediately available as I had a disk > crash and lost it. > - There will, of course, be a small minority of people who will reject > tropical beachfront paradise lifestyle as their primary residence and > instead choose to live in forests chopping wood, etc. I myself expect to > be among that number but I am about 6 sigma out in a number of ways. Your > average wife will look at the urban amenities, spacious condo, high income, > intense social life, abundant food and beach front tropical lifestyle and > simply leave her husband if he insists on "Green Acres". > > > > > On Thu, Jun 12, 2014 at 1:08 PM, Jed Rothwell <[email protected]> > wrote: > >> James Bowery <[email protected]> wrote: >> >> Even if cold fusion brings the cost per kWh to 5 mil, it will still make >>> sense to locate floating photobioreactors producing agricultural feedstocks >>> in the tropical doldrums protected by artificial floating atolls supporting >>> beachfront real estate enjoying enormous amounts of electrical energy per >>> capita. >>> >> >> I think 5 mill = 0.005 cents. Anyway, no this does not make sense. This >> is like saying that even though we now have 2 terabyte disks that cost >> $100, it makes sense to use a 10 MB disk that cost me $20,000 in 1978. >> >> "Photobioreactors producing agricultural feedstocks" may be useful for >> the feedstocks they produce, but the energy will far more expensive than >> cold fusion, and it will be annoying and expensive to harvest, so people >> will throw it away. >> >> People in rural areas who own ~20 acres of forested land can easily cut >> enough firewood to heat their houses. I know people who do that. It is >> cheaper than heating with natural gas or electricity. You only have to pay >> for the fuel for the buzz saw and log splitter, which consume much less >> energy than the logs they produce. However, cutting and splitting wood is a >> lot of work. You would not do it to save money if the alternative was cold >> fusion space heating that cost you $0.0000001 per year in fuel. People will >> still need to cut up fallen trees to maintain a healthy forest, but they >> will have no economic use for the firewood. >> >> (Granted, saving money is not the only reason people burn wood. Some >> people do it out out of nostalgia, or because they enjoy seeing a fire. >> Some cut wood for exercise. Some might burn it just to get it out of the >> way.) >> >> - Jed >> >> >
