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 Production of Algal Bio-fuel and Use of the Exclusive Economic Zone

 Production of Algal Bio-fuel and Use of the Exclusive Economic Zone

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228



MASAHIRO NOTOYA



In this design, the extensive stable supply of biomass materials is realized

with a first premise. The way of thinking and conditions at the unique location

of the vast exclusive economic zone of Japan is suited for algal culture and

subsequent biofuel production. Views of new, eco-friendly synthetic technology

development in global and marine resource preservation will help in Japan’s

global contribution.

8. References

Ministry of the Environment, Government of Japan (1994) National survey on the natural environment. 1–400 (in Japanese).

Murata, Y. (1980) Photosynthesis and production, In: S. Miyachi and Y. Murata (eds.) Photosynthesis

and Dry Matter Production. Rikougakusha, Tokyo, pp. 475–510 (in Japanese).

Okamura, D. (2003) Sargassum yezoensis, In: M. Notoya (ed.) Seaweed Marine Forest and Its Developmental Technology. Seizando-Shoten, Tokyo, pp. 75–81 (in Japanese).

Taniguchi, K. and Yamada, Y. (1978) Ecological study on Sargassum patens C. Agardh and S. serratifolium C. Agardh in the sublittoral zone at Iida Bay of Noto Peninsula in the Japan Sea. Bull.

Jpn. Sea Reg. Fish. Res. Lab. 29: 239–253.

Taniguchi, K. and Yamada, H. (1988) Annual variation and productivity of Sargassum horneri population in Matsushima Bay on the Pacific Coast of Japan Sea. Bull. Tohoku Reg. Fish. Res. Lab.

50: 59–65 (in Japanese).

Worm, B., Barbier, E.B., Beaumont, N., Duffy, J.E., Folke, C., Halpern, B.S., Jackson, J.B.C., Lotze,

H.K., Micheli, F., Palumbi, S.R., Sala, E., Selkoe, K.A., Stachowicz, J.J. and Watson, R. (2006)

Impacts of biodiversity loss on ocean ecosystem services. Science 314: 787–790.

Yokohama, Y., Tanaka, J. and Chihara, M. (1987) Productivity of the Ecklonia cava community in a

bay of Izu Peninsula on the Pacific Coast of Japan. Bot. Mag. Tokyo 100: 129–141.



Biodata of Christopher J. Rhodes, author of “Biofuel from Algae: Salvation from

Peak Oil?”

Professor Chris J. Rhodes is currently a visiting professor at the University of Reading and Director of Fresh-Lands consulting. He was awarded a D.Phil from the

University of Sussex in 1985 and a D.Sc in 2003. He has wide scientific interests (www.fresh-lands.com) which cover radiation chemistry, catalysis, zeolites,

radioisotopes, free radicals, and electron spin resonance spectroscopy, and more

recently have developed into aspects of environmental decontamination and the

production of artificial fuels. He has published more than 200 peer-reviewed

papers and three books.

E-mail: chris.rhodes@rba.co.uk



229

A. Israel et al. (eds.), Seaweeds and their Role in Globally Changing Environments,

Cellular Origin, Life in Extreme Habitats and Astrobiology 15, 229–248

DOI 10.1007/978-90-481-8569-6_14, © Springer Science+Business Media B.V. 2010



BIOFUEL FROM ALGAE: SALVATION FROM PEAK OIL?



CHRISTOPHER J. RHODES

Fresh-Lands, P.O. Box 2074, Reading, Berkshire, RG4 5ZQ,

UK



1. Introduction

There is practically nothing in the modern world that does not depend on the

resource of plentiful, cheap oil. The majority of crude oil is refined into fuel for

transportation, but it also provides a feedstock for a myriad of industries, producing products ranging from plastics to pharmaceuticals. In total, it is reckoned that

worldwide some 86 million barrels of oil are consumed daily, which amounts to just

over 31 billion barrels a year. Around one quarter of all oil is used in the USA, which

was formerly the world’s main oil-producing nation. Now that accolade is with

Saudi Arabia, which delivers an almost ten million barrel daily aliquot to the world

oil markets, while Russia exhumes an almost equal quantity. In 1999, the price of a

barrel of oil was $12, but reached almost $150 in the summer of 2008 preceding a

world stock market crash and a fallback to $25 a barrel (Rhodes, 2008). The price

rose during the following year and, writing in August 2009, it is now around $70 a

barrel. There are many factors held culpable for such frenetic activity in the marketplace, including a seemingly inexorable demand for oil (and indeed all kinds of

energy resources) from rising economies such as China and India, a weakening US

dollar, and that oil is becoming harder to produce, as a general principle. Over all

of this looms the specter of peak oil, which is the point at which production meets a

geological maximum, and beyond which it must relentlessly fall. The combination

of these factors must culminate in a gap between rising demand and ultimately falling supply. Within a decade or less, the world economies will no longer be able to

depend on some limitless growth in oil output. For these reasons, attention is being

turned toward “Alternatives,” which ideally are also “Renewables,” but the issue of

biofuels is more complex than is generally realized, and it is at best a partial solution bearing its own attendant environmental costs (Rhodes, 2005).

In addition to the simple fact that growing fuel crops must inevitably

compete eventually for limited arable land on which food-crops are to be grown,

there are vital differences in the properties of biofuels, e.g., biodiesel and bioethanol,

from conventional hydrocarbon fuels such as petrol and diesel, which will necessitate

the adaptation of engine designs to use them; for example, in regard to viscosity

at low temperatures, e.g., in planes flying in the frigidity of the troposphere. Raw

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CHRISTOPHER J. RHODES



ethanol needs to be burned in a specially adapted engine to recover more of its

energy in terms of tank to wheels miles, otherwise it could deliver only about 70%

of the energy content of petrol, pound for pound in accordance with its lower

enthalpy of combustion (29 MJ/kg) than is typical for an oil-based fuel like petrol

(gasoline) or diesel (42 MJ/kg) (Rhodes, 2005).

Of the various means that are being considered, at least in terms of growing our way out of the oil crunch, is making biofuel from algae. There are many

advantages claimed as we shall see, but in particular, the quoted yields of oil

that might be derived from algae per hectare are high, even when compared with

those from high-oil-yielding plants such as jatropha and palm, which translate

to around 6 t of diesel per hectare (see Section 6). Most biofuel in Europe is

biodiesel and is made, for example, from rapeseed oil, which yields perhaps 1 t

of diesel per hectare. In contrast, it is reckoned that some species of high-oilyielding algae might furnish more than 100 t of diesel per hectare – an attractive

prognosis indeed, since an area, say the size of the southern UK, could fuel the

entire world (Rhodes, 2005). Algae offer further advantages that they can be

used to absorb CO2 from smokestacks at fossil-fuel-fired power stations, they

can be grown on saline waters or wastewaters (cleaning the latter in the process),

and furthermore there is no necessity to use arable land for algae production

since the tanks they are grown in can be placed anywhere, including brownfield

land or on the open ocean. Thus, the competition between fuel and food production is avoided.

The author attempts an overview of some specific aspects of a subject that

is, however, not quite as straightforward as it first appears.

2. The Peak Oil Problem

The prediction of peak oil was made in 1956 by Marion King Hubbert (Hubbert,

1956), a geophysicist working for the Shell Development Corporation. Hubbert predicted that the lower 48 states in the USA would peak (hit maximum production)

during 1965–1970, depending on his estimate of the total volume of the reserve.

At that time, the USA was awash with oil and his prediction was not taken seriously.

Hubbert’s analysis is based on the logistic function, the first derivative of which

gives a peak. Mathematically, this kind of curve can be represented by the logistic

differential equation (1).

dQ/dt = P = k(1 – Q/Qt )Q



(1)



In Eq. (1), P is the production rate, as shown by its equality to the rate of change

of cumulative production Q (i.e., the sum quantity of oil recovered from a given

source to date), Qt is the total amount of oil that will ever be recovered from it,

and k is the logistic growth rate (a sort of % compound interest). In Hubbert’s

original paper (Hubbert, 1956), he assumed two scenarios for the lower 48 states

in the USA: (1) there were 150 billion barrels worth of oil and (2) there were 200



BIOFUEL FROM ALGAE: SALVATION FROM PEAK OIL?



233



billion barrels as a total recoverable reserve, Qt. In those days before computers,

he simply reckoned the amount of oil represented by each square on his sheet of

graph paper, and drew a curve by hand that enclosed an area equal to the estimated volume of the reserve. For case (1), he predicted that the peak in production

would arrive in 1965 and for (2) around 1970. Thus, the method was not predictive

of the volume of oil that would be recovered in total; this had to be reckoned first.

In fact, US production peaked in 1971, so establishing both his fame and credibility in the basic method. In a later paper (Hubbert, 1982), Hubbert surveyed

the mathematics behind all this, from which an alternative and predictive method

coined the Hubbert Linearization (Deffeyes, 2005) was derived. The basis of this is

that Eq. (1), which is a quadratic, can be rewritten in the form of Eq. (2), which is

a linear equation of familiar form y = mx + c.

P/Q = k(1 – Q/Qt )



(2)



By plotting annual production divided by cumulative production (i.e., P/Q) versus

cumulative production alone (Q), a straight-line plot is obtained, with a y-axis

intercept equal to k and a slope of −k/Qt. Thus, both essential parameters of the

logistic peak, k and Qt, may be estimated without prior assumptions, an improvement

on the original approach (Hubbert, 1956). The method is still used extensively in

the oil industry, although now with modern PCs, it is easy to fit directly logistic

and all other kinds of functions to oil production data using programs like Origin.

Having established values for k and Qt, they can be used to construct the logistic

curve with considerable accuracy. Because of the symmetry of the curve, when

the peak is reached, half the reserve has been extracted, beyond which production

falls inexorably. For the entire world, a value for Qt of around two trillion barrels

is estimated, of which we have used close to half. It is expected that once the

peak is reached, there will be a decline in world oil production by 3% per annum.

This approach is not without its critics, however. Some maintain that it is an

oversimplification, and does not allow for future discoveries of oil or the production of unconventional oil and that it is more likely that the postpeak outcome

will be a more steady plateau followed by a gradual depletion in supply rather

than a mirror-fall of the growth phase. The oil industry actually uses a number of

methods of geophysics, e.g., seismic measurements, to estimate the volume of a

reserve, and their final predictions are often based on a combination of physical data

and various kinds of mathematical and numerical modeling procedures, including

“Hubbert.”

Various estimates have been given for the time of arrival of peak oil. If all

production, ignoring tar sands and natural gas liquids (NGL), is considered, the

peak famously reckoned by Kenneth Deffeyes (2005) to arrive on November 24,

2005 (thanksgiving day!), is predicted. If all production including NGL is

included, the peak shifts forward to mid-2006. All studies that place peak oil in

2010 and beyond use other methods, but generally consider the rates of depletion

of existing oil fields and projections about developing fields. Such studies are

termed “bottom-up analysis.” Chris Skrebowski, a researcher for the Energy



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