302 Marine Macro- and Microalgae: An Overview
optimistic projections over the last decades, the scale of microalgal commercial cultivation is still
quite small (compared, for example, to agriculture). The economic and environmental impacts of the
microalgae industry have been, therefore, quite small. However, as the scale of activities increase in the
future, fueled by increases in productivity and market size and lowering of costs, we expect that these
impacts will increase in significance.
Microalgal commercial products at present
Apart from “green water” production, touched upon in the previous section, most photoautotrophic
commercial microalgal production consists of relatively high value products such as astaxanthin
and β-carotene (from Haematococcus and Dunaliella) and whole cell biomass (such as Arthrospira,
Nannochloropsis, and Chlorella). These are, at this point in time, specialty products, not commodities.
Out of the myriad of proposed microalgal products, many will continue to be specialty products. Two
families of products, however, have the potential to truly change the scale of microalgal cultivation:
feeds and fuels. As these new products come into being, we expect that the industry’s environmental and
economic impacts will become significant.
The cost of microalgae and microalgal products on the present commercial scale
Producers of commercial microalgal products are not likely to share their true production costs for
competitive reasons. However, based on pricing and availability of commercial microalgal products
educated guesses can be made. Depending on the process used, microalgal biomass production costs
range over three orders of magnitude. Here we consider two established commercial microalgal products,
Spirulina biomass (Arthrospira) and astaxanthin (Haematococcus), and we compare them to the estimated
costs of producing “green water” (see above, Neori 2011).
First, we consider the production costs of Spirulina biomass. Spirulina has been cultivated
commercially for over 40 years in the US and production has been expanding in Asia, especially China
(Yun-Ming et al. 2011). Spirulina has many applications (see later sections) but is mainly being sold as a
nutritional supplement. Because of its growth and physical characteristics (high alkalinity medium, large
size), it is a relatively inexpensive biomass to produce that needs relatively little processing. Several
authors have estimated the cost of producing Spirulina biomass at about US$3–5/kg depending on the
locale (e.g., Grewe and Pulz 2012).
Second, we consider the production costs of significantly more costly microalgal products, such
as astaxanthin from Haematococcus. Haematococcus astaxanthin has been produced commercially for
over 15 years (Olaizola 2000). Haematococcus is much costlier than Spirulina to produce: it requires an
enclosed PBR growth phase, has a higher probability of culture crashes than Arthrospira cultures and
requires more complex processing, including cell cracking and extraction. Estimates of production costs
range up to US$100/kg dry biomass (see for example, Carlsson et al. 2007).
Taking those biomass production costs, we can loosely estimate the cost of microalgal products
which may accumulate in microalgal biomass at different concentrations (Table 1). Clearly, production
of microalgal biomass is quite expensive if one needs to control the population composition (as opposed
to “green water”) and if one does not use an extremophile strain (like Arthrospira). The cost data may
help explain why some products have not yet made it to market. For example, algal biofuel precursors
from a non-robust strain (even if highly lipid accumulating: 20–50% is commonly claimed) can be
expected to cost > US$200 per kg. From a protected strain, but less lipid enriched, it might cost as little as
US$20 per kg. This explains why the products that have reached the market tend to be very valuable, that
is, can demand a high price (i.e., higher than the cost of production).
Economic impacts
The development of the microalgal technology industry has spurred growing economic activities. As
indicated earlier, several US$Bn per year would appear to be a reasonable size for the worldwide market
optimistic projections over the last decades, the scale of microalgal commercial cultivation is still
quite small (compared, for example, to agriculture). The economic and environmental impacts of the
microalgae industry have been, therefore, quite small. However, as the scale of activities increase in the
future, fueled by increases in productivity and market size and lowering of costs, we expect that these
impacts will increase in significance.
Microalgal commercial products at present
Apart from “green water” production, touched upon in the previous section, most photoautotrophic
commercial microalgal production consists of relatively high value products such as astaxanthin
and β-carotene (from Haematococcus and Dunaliella) and whole cell biomass (such as Arthrospira,
Nannochloropsis, and Chlorella). These are, at this point in time, specialty products, not commodities.
Out of the myriad of proposed microalgal products, many will continue to be specialty products. Two
families of products, however, have the potential to truly change the scale of microalgal cultivation:
feeds and fuels. As these new products come into being, we expect that the industry’s environmental and
economic impacts will become significant.
The cost of microalgae and microalgal products on the present commercial scale
Producers of commercial microalgal products are not likely to share their true production costs for
competitive reasons. However, based on pricing and availability of commercial microalgal products
educated guesses can be made. Depending on the process used, microalgal biomass production costs
range over three orders of magnitude. Here we consider two established commercial microalgal products,
Spirulina biomass (Arthrospira) and astaxanthin (Haematococcus), and we compare them to the estimated
costs of producing “green water” (see above, Neori 2011).
First, we consider the production costs of Spirulina biomass. Spirulina has been cultivated
commercially for over 40 years in the US and production has been expanding in Asia, especially China
(Yun-Ming et al. 2011). Spirulina has many applications (see later sections) but is mainly being sold as a
nutritional supplement. Because of its growth and physical characteristics (high alkalinity medium, large
size), it is a relatively inexpensive biomass to produce that needs relatively little processing. Several
authors have estimated the cost of producing Spirulina biomass at about US$3–5/kg depending on the
locale (e.g., Grewe and Pulz 2012).
Second, we consider the production costs of significantly more costly microalgal products, such
as astaxanthin from Haematococcus. Haematococcus astaxanthin has been produced commercially for
over 15 years (Olaizola 2000). Haematococcus is much costlier than Spirulina to produce: it requires an
enclosed PBR growth phase, has a higher probability of culture crashes than Arthrospira cultures and
requires more complex processing, including cell cracking and extraction. Estimates of production costs
range up to US$100/kg dry biomass (see for example, Carlsson et al. 2007).
Taking those biomass production costs, we can loosely estimate the cost of microalgal products
which may accumulate in microalgal biomass at different concentrations (Table 1). Clearly, production
of microalgal biomass is quite expensive if one needs to control the population composition (as opposed
to “green water”) and if one does not use an extremophile strain (like Arthrospira). The cost data may
help explain why some products have not yet made it to market. For example, algal biofuel precursors
from a non-robust strain (even if highly lipid accumulating: 20–50% is commonly claimed) can be
expected to cost > US$200 per kg. From a protected strain, but less lipid enriched, it might cost as little as
US$20 per kg. This explains why the products that have reached the market tend to be very valuable, that
is, can demand a high price (i.e., higher than the cost of production).
Economic impacts
The development of the microalgal technology industry has spurred growing economic activities. As
indicated earlier, several US$Bn per year would appear to be a reasonable size for the worldwide market