Scheer Solar Economy Renewable Energy for a Sustainable Global Future (Earthscan, 2005)

EXPLOITING SOLAR RESOURCES 71

the manufacture of plant-derived plastics. In essence, supply chains may be particularly short where the required plant material can be efficiently grown in the vicinity of the processing plant, but are of necessity longer where a highly specific material is required which grows only in certain regions, or can only be efficiently produced in the required quantities in those regions.

The basic principle, however, is the same: most countries must import fossil fuels and mineral resources for lack of their own reserves, whereas most solar resources can be produced domestically, as evidenced by countless examples of food crops initially native to one region, but now grown almost the world over. Potatoes and maize, for instance, were originally natives of the Americas; now they grow in almost every corner of the world. The same goes for rice and bananas, originally from Indochina, or beans from the Andes or wheat from central Asia. Of course, not all plant species can be so transplanted; local climates vary too widely. Nevertheless, the possibility exists for a relatively large number of species, especially where insolation, precipitation and land quality are similar. In any case, almost every region offers its own specific palette of useful crops.

Biomass remains unique among the renewable energy sources in being reliant on a supplier of primary energy. That being the case, it is entirely conceivable, despite the economic advantages to be obtained from proximity of production and processing to power plants, that biomass exploitation could follow the pattern of global business concentration and associated dependency relationships familiar from the fossil fuel industry. Indeed, multinational corporations are already buying up vast tracts of agricultural and forest land in order to secure their future position as suppliers of raw materials and energy. In this regard they are following the negative example of Brazil, where bioalcohol for millions of vehicles is produced from sugar beet grown in gigantic plantations. To get an idea of the potential risks, one only has to cast an eye over the foodprocessing industry, which has undergone a long-running and heavily internationalized process of business concentration, despite the requirement to produce locally enforced by the need for agricultural land.

72 CAPTIVITY OR LIBERATION

The primary tools of would-be monopolists were direct production and supply contracts with agricultural enterprises. The first stage was to squeeze ever lower prices from the producers. Then came ‘vertical integration’, as the foodstuff companies moved towards direct control of agricultural production – dictating exactly which fruits the farmer should grow for optimal industrial use. This second stage followed on logically from the first, after the initially relatively independent farmers were forced into dependency or to relinquish their farms entirely. The third stage was the monopolization of plant and animal seed. Further expansion of this monopoly is sought through the patenting of genes, particularly in response to pressure from chemicals companies, a subject examined in more detail in Chapter 7. These developments were additionally facilitated by tax breaks for the international trade in agricultural produce and latterly by recent agreements on world trade, which do not distinguish between agricultural and industrial goods, as discussed in more detail in Chapter 9. Finally, the industrialized countries also grant direct subsidies to food exports. The WTO treaty does stipulate that these subsidies must be removed, the only positive aspect of WTO regulations in the agricultural sector.

Is it not then highly likely that these structures will also govern the increasing use of biomass as a source of energy and resources? It would not be the first time that the wrong approach has triumphed over economic and environmental sense because large corporations have used their overbearing influence on governments and parliaments to promote their own interests. Agriculture is one of the most prominent examples of this. If it were simply a question of securing the resource base for the post-fossil-fuel age, protecting the atmosphere from the trace gases emitted in fossil fuel extraction, processing and combustion, and overcoming the dependency of energy-importing countries on the very few exporters, then even biomass exploitation under the control of a small number of corporations would be preferable to fossil fuel use. In both cases the processing and marketing structures would be transnationally concentrated, but the advantages of biomass over fossil fuels would still be realized. However, a process of

EXPLOITING SOLAR RESOURCES 73

accelerated concentration would also bring dramatic social consequences for rural areas, run the familiar risk of reckless and extremely unbalanced farming methods and cause a global redistribution of nutrients equally fraught with environmental difficulty. The gigantic shipments of animal feed from the USA to Europe also export mineral nutrients, thus depleting US agricultural land and placing a strain on the capacity of European countries to absorb them.

The decisive difference between fossil fuel energy and fossil and mineral resources on the one hand, and plant-derived resources on the other, however, lies elsewhere. In the first case, the formation of global supply chains under the rule of transnational corporations is inevitable and irreversible; in the second, global supply chains and transnational business concentration are by no means inevitable and, where this has occurred, reversible. The determining factor is: who latches onto plant-derived resources and how? In the end, the politically determined framework for the energy and agricultural industries determines whether the exploitation of biomass for food, energy and raw materials results in long or short supply chains, industrial concentration or decentralization. In other words, concentration can be avoided, especially with radical reform of agricultural and energy policy. Where concentration and monopolization has taken place, this can be reversed as long as the land remains fertile or can be reclaimed by politically imposed land reform or regional market regulation.

Supply chains for industrial electricity generation from renewable resources

Where concentrated supplies of energy are available, it is more cost-effective to produce electricity using large turbines than using smaller power plants of the same type. Due to their wide distribution, this applies to renewable sources in only four cases:

1biomass, which can fire power stations of up to 100 megawatts (MW) capacity;

74 CAPTIVITY OR LIBERATION

2highly concentrated quantities of water, such as strong river currents or straits, large natural waterfalls like Niagara, or artificial heads created by dams. The latter involves extreme interference in natural cycles, and is also problematic because of the risk of dam failure endangering entire regions;

3tidal power, generating power from the ebb and flow of the tide in coastal regions; and

4solar thermal plants, which either use collectors to concentrate solar heat to produce steam to drive turbines in the conventional way, or combine a large area of transparent film with a chimney-like tower to create an updraft through the tower. The updraft powers turbines mounted at the base of the tower.

In these cases, the electricity supply chain begins at the power station. As with fossil fuel or nuclear power, the electricity must then be fed through high-, mediumand low-voltage cables before it can be used to power lights and motors, giving a total of five links in the chain.

The supply chain for direct generation from renewable energy sources

The advantage of shorter supply chains is especially true of PV. Sunlight can be converted into electrical energy all over the world and with the lowest distribution costs of all generation technologies. As electricity is the most flexible of all secondary energies, suitable for the production of artificial light, powering machines and motors, heat pumps and refrigeration systems as well as for driving industrial processes, Harry Lehmann terms PV the ‘prima donna’ of the energy world.6 It is only the (as yet) relatively high production cost of solar panels that distracts from their potential economic superiority.

In this case, the supply chain begins with the installed solar panel, which directly converts sunlight into electricity – without moving parts and thus almost without wear and tear, completely silently and without any emissions whatsoever. Of

EXPLOITING SOLAR RESOURCES 75

course, the panels must still be manufactured beforehand, a process consisting essentially of the production of the necessary material (currently predominantly silicon), cell manufacture, panel assembly, manufacture of the inverters to convert the direct current produced into alternating current, and lastly the installation of the panels themselves. But the production chain for the generating plant has not been subject to particular scrutiny in the analysis of fossil fuels either – neither for the power stations nor for the refineries or transportation. Where solar panels are used in isolation to produce electricity for consumption on-site, the generation process is then already almost compete, because the current need only be piped through the internal cabling of the house or device to power lights and machines. Electricity with no supply chain! There are only a few people who appreciate the fundamental importance of this.

Even where PV electricity is fed into the grid and thus embedded in a supply chain, the chain is still very short. The current need only be piped down low-voltage cables because it is generated in small quantities in numerous locations, which does not result in high voltages. Even power-station electricity reaches the end-user ultimately over low-voltage cables. PV electricity avoids the detours via the transformers and hightension cabling necessary for fossil fuel energy.

The supply chain for wind power also starts at the wind turbine. If used autonomously, then, as with PV, there is only one link in the chain. Further links arise where the power is fed into the grid, depending on how often the current has to be transformed before it reaches its destination.

The supply chain for solar hydrogen

The use of electricity from renewable sources to electrolyse water into its constituent hydrogen and oxygen offers significant scope for expanding the spectrum of renewable energies. By this means energy can not only be stored, but the hydrogen can also be used as fuel to drive industrial processes or as a raw material for the chemicals industry. Discussions of these possibilities have hitherto centred on the heavy industrial

76 CAPTIVITY OR LIBERATION

approach – using large-scale solar power plants in the Sahara or large-scale hydro in Canada to manufacture the hydrogen, which would then need to be transported to Europe or the USA. Little or no consideration has hitherto been given to the separation of hydrogen in local small-scale electrolysis plants using renewable energy, or its extraction from biomass.

Yet this is precisely what must be considered, for otherwise the supply chain for hydrogen becomes as long as for fossil fuel or nuclear energy. The supply chain for centralized production begins with electricity generation in large-scale hydro or solar thermal plants. The electricity must then be fed over highvoltage cables to the electrolysis plant, where hydrogen is separated and subsequently liquified to render it transportable. The liquid hydrogen must then be stored in large storage tanks in the vicinity of harbours, before being shipped to its destination where it must once again be stored. Thence it can be distributed to power stations, garages and households, who place it in interim storage before it is finally used. That makes a total of 11 links in the chain, including the final conversion into energy. For regional production, by contrast, the chain is shorter, as electrolysis, liquifaction and storage can be colocated, and even electricity generation and electrolysis can be combined, which would render the development of a comprehensive hydrogen transport infrastructure unnecessary.

The economic logic of the solar energy supply chain

Fossil fuel and solar energy generation are intrinsically very different processes, and the opportunities they present for maximizing availability and efficiency – with respect to both resource consumption and financing strategies – are correspondingly diverse. Besides the differing environmental impact, the disparities between the supply chains demonstrate just how absurd it is to evaluate the economic potential of energy sources solely on the basis of the capital cost of the power generation plant required. It is because of such absurd reasoning that there has been such reluctance to exploit the potential of renewable resources.

EXPLOITING SOLAR RESOURCES 77

Figure 2.1 compares the supply chains for fossil fuels and renewable energies, from which the following conclusions can be drawn:

•The shorter the supply chain – ie, the smaller the number of distinct processing steps involved – the greater the scope for reducing the costs of energy generation. If improved solar technologies can be introduced on a large scale, they represent not just the least environmentally damaging strategy for meeting energy needs, they are also potentially the most productive and thus the most economic solution. For this to happen, it is insufficient merely to recognize the benefits of solar energy. Technologies and strategies must be developed to exploit its advantages to the full. Insufficient progress on this front is the reason why the greatest potential economic benefit of renewable resources has not yet been systematically exploited.

As long as they remain embedded within the conventional framework for energy generation, providers and consumers of energy from renewable resources will continue to pay the costs of fossil fuel supply and distribution networks. The potentially decisive advantage that renewable resources have over conventional fossil fuels will continue to go unexploited. If the switch to renewable resources simply replaces elements of the established fossil fuel structure, this will introduce a systemic bias that will hamper the growth of the renewables sector, confining it to a peripheral role within the energy industry for some time to come. Effective use of renewable resources requires a radical rethink of the supply and distribution network – simply copying the established structure will not work. The construction and operation of the distribution grid, for example, typically constitutes more than half the costs of an electricity supply. It is in the elimination of precisely these factors that the greatest opportunity for productivity gains from renewable energy resources lies.

It follows from this that productivity gains from renewable resources cannot be realized through the construction of multi-megawatt power plants with sprawling distribu-

78 CAPTIVITY OR LIBERATION

tion networks. That is not to say that there is no place for solar thermal power plants. What is does imply is that such plants should not be used as the core of an inter-regional

– or even international – distribution grid. The ideal use for a solar thermal power station would be to serve large towns and cities in its immediate vicinity – for example, Cairo’s power needs could be supplied by a plant located in the nearby desert.

•On this basis, one criterion for evaluating the various technologies available for exploiting solar energy will be their potential for shortening or even completely eliminating the energy supply chain. On-site generation using PV cells, for example, may potentially be far more economic than large-scale generation plant.

•One decisive advantage for renewable energy in the future lies in the ability to generate electricity at minimal technological and infrastructural cost. Because electricity is such a flexible tool, the demand for electricity will grow at an increasing

rate, at the expense of other sources of energy. Within the current system, it is simpler to supply fuel for combustion when and where the energy is required. Converting the same fuel into electricity requires additional process steps, and thus is more laborious and technologically complex. With renewable resources, the opposite applies: electricity generation using PV and wind turbines is technologically the simpler route, whereas producing combustible fuel is more complex and long-winded. This reversal provides the template for the energy revolution to come.

The complexity of fossil fuel and solar power generation

Renewable energy is regarded as uneconomic primarily because of the allegedly greater material cost of local power generation over centralized power stations. This reasoning is specious, as it neglects to consider the long supply chains involved in fossil fuel energy and the concomitant material cost of fossil fuel

PV		PV installation		Distribution

End-user (on-site generation)

Wind		Windfarm
power

End-user (on-site generation)

National grid Distribution (medium (low voltage) voltage)

Biomass

Planting

Harvest

Shipping

Pressing

Shipping

Power

Gasification

station

Conversion to

Garages

pellets

• Recycling of

residues

National grid Distribution (medium (low voltage) voltage)

Crude oil

Extraction

Shipping

Refining

Shipping

Oil-fired

National grid

National grid

Distribution

Storage

power

(high voltage)

(medium

(low voltage)

Garages

station

voltage)

Oil traders

Coal

Mining

Refining

Shipping

Coal-fired

National grid

National grid

Distribution

power station

(high voltage)

(medium

(low voltage)

• Disposal of

voltage)

ash

Nuclear

Uranium

Shipping

Ore

Shipping

Enrichment

Shipping

Nuclear

National grid

National grid

Distribution

mining

extraction

• Disposal of

power

(high voltage)

(medium

(low voltage)

enriched

station

voltage)

uranium

• Intermediate

storage

• Final

storage

• Reprocessing

ESOURCESR OLARS XPLOITINGE

Figure 2.1 Comparison of electricity generation from fossil fuels and renewables

79

80 CAPTIVITY OR LIBERATION

extraction and transport. It also takes no account of the relative complexity of the different generation technologies. Electricity generation from fossil fuels involves a considerably greater number of processing steps, resulting in proportionately greater technical costs (see Figure 2.2). In a fossil fuel power station, the first step is to convert chemical into heat energy through combustion (in a nuclear power plant the heat is derived from nuclear fission). Three further conversion processes follow: thermodynamic energy transfer to turn water into steam; conversion into mechanical energy as the steam drives the turbine; and finally conversion of mechanical energy into electrical in the generator. At the same time, the mechanical plant must also be cooled.

PV electricity generation, by contrast, involves only two steps: conversion of incident sunlight into direct current in the cell itself, followed by inversion to produce alternating current. In the case of wind power, the wind is converted into mechanical energy by the rotors, which in turn drive the generator to generate current. No cooling system is needed. Quite clearly wind turbine plant is not only easy to install; it is also more amenable to standardized production, and does not require operational personnel, aside from occasional maintenance work.

The fact that supply chains for solar power are short and the generation plant relatively simple really does beg the question of why generations of scientists and technicians have refused to accept it as an alternative, instead setting store by more laborious techniques, even preferring such extremely complex and technically fraught propositions as controlled nuclear fusion. Whereas complex technological solutions are placed on a pedestal, comparatively simple technologies are regarded with studied distrust, too backward for the modern, progressive age. Imaginative reservations are constructed in respect of ‘simplistic’ techniques, while justifications for hightech approaches are grossly oversimplified.