Howard Wilcox's estimation of the prospects for farming the ocean were based upon a 2% efficiency for converting solar energy into plant material, a 5% efficiency for production of human food, and a 50% efficiency for the production of fuel and other products.  Assuming these numbers are correct, one square mile of sea surface would produce enough food to feed 3,000 to 5,000 persons, and enough energy to support more than 300 persons at current U.S. per capita consumption levels.  Since the oceans contain 80 to 100 million square miles of arable surface water, the marine farms could support a world population of more than twenty billion persons.  NMI's estimate of 1% efficiency for solar conversion into marine biomass was considerably more conservative than Wilcox's earlier number.  This number was later confirmed by harvest data taken from the Elwood farm.

The contrast between optimistic and conservative views of maricultural potential is summarized by illustrations of existing and future farms that have been published.  These serve as "samples" of past views and draw attention to specific aspects of the GRI program.  For example, in 1974, an illustrated article in Newsweek carried the heading "Four-H Frogmen" and a quotation from Wilcox that "It's not high technology... we're just talking about plain old plants growing."  Wilcox's initial optimism and "low tech" approach was misleading, to say the least, especially considering that the 1972 program began with the primary objective of proving that macroalgae (kelp) could be farmed.  It was not until 1982-83 that NMI produced the first (and only) yield data.  Unlike the Wilcox/GE group, NMI began their experiments with the assumption that Macrocystis was exceedingly complex and hence difficult to cultivate.  NMI's results justified this approach, as they concluded that the success of marine farms hinged upon a sound program of hydrodynamic measurements.  In other words, marine farming entailed a lot more than simply tying a plant to a structure anchored in the ocean.

Criticism of the GRI project also demonstrated the general lack of knowledge in the U.S. about marine farming.  For instance, a Washington Post cartoon appearing during the project, highlighted the loss of 100 kelp plants attached to Wilcox's first test farm.  What the author failed to understand was than even though giant kelp are large and tree-like, they are really ephemeral.  In fact, up to a third of all plants in California beds are annually lost to storm and grazing damage.  The loss of all plants in an experimental planting is not unusual, depending upon the environmental conditions.  Here again, the focus on farm structure as opposed to the actual crop drew attention away from the most important aspect of marine farming—the plants themselves.

Despite the misconceptions that plagued the Ocean Food and Energy Farm, Wilcox's projection of 2% efficiency in conversion of sunlight to energy was not realistic.  As mentioned above, NMI's near-shore growth data demonstrated a 1% efficiency (conservative estimate), a number that confirms the viability of marine biomass as a source of energy.  NMI also demonstrated that Macrocystis has an exceedingly high rate of biomass production (fifteen dry ash-free tons per acre per year), and that the plants can withstand quarterly harvests where up to half of the biomass is removed.  Furthermore, survival of plants following repeated harvesting showed that substantial yields were possible without changing the standing crop.

Review of the marine biomass program provides valuable lessons for future development of marine farming.  Of the many difficulties that plagued initial efforts to farm the sea, one in particular, stands out—the lack of communication between engineering and biological communities.  The project began with the assumption that marine farming would not be technically difficult.  Wilcox's statement that "It's not high technology... we're just talking about plain old plants growing," illustrates this lack of understanding.  Ten years later, after the work of two contractors and several major experimental farming efforts, there was still no yield data for farmed Macrocystis.   Plants were entangled with the farm structures, consumed by fish, infected, or dislodged and destroyed by storms.  By 1980, it was apparent that building a "false bottom" for kelp plants in the open-ocean was not a "low-tech" task.  Attempts to protect the structures with a fabric current shield (ripped away) also met with failure.  While marine engineers learned from the QAM and grid experiments, biologists were unable to obtain any significant growth data from the experiments.

Many of the problems associated with marine farming were due to constraints on the overall Marine Biomass Program.  In particular, Wilcox's original concept required an enormous amount of marine biomass, near-shore work was not deemed to be worthwhile.  This resulted in an approach that required both engineers and biologists to "walk before they could crawl," an obstacle that contributed to the lack of data generated by the early open-ocean experiments.  Without this crucial growth data, there was no way of testing Wilcox's theory about the biomass potential of marine farming.  NMI produced these data by planting and harvesting a near-shore marine farm.  Current efforts to revive the program should take particular care not to overlook the experience of earlier investigators.  Marine plant specialists must be involved from the very beginning and should play an active role in the design of farming structures.  From an engineering perspective, the grid and QAM experiments were somewhat useful in that they highlighted the many problems encountered in placing artificial substrates in deep water.  However, the lack of significant growth data demonstrated that the success of marine farming did not hinge solely upon the ability to anchor the structures in the ocean.  In particular, engineers needed to account for the hydrodynamic requirements of the marine plants that they were attempting to grow.  Future project managers must place the plants first in order to succeed in the production of marine biomass.