Northeast Regional Center Director's Report

Steven C. Wofsy, Director

Reducing Emissions of Greenhouse Gases by Alternative Energy Sources

Daniel M. Kammen, Princeton University
Richard Wilson and Alexander I. Shlyakhter, Harvard University

Table of Contents

Objectives: Renewable energy technologies such as solar photovoltaic installations for producing electricity, wind energy systems, and - - at a vastly different energy scale - - nuclear power facilities, have each been touted as solutions to local or regional energy shortages that produce not greenhouse gas emissions. These systems, and many others, have been championed by some as environmental saviors and denigrated by critics as impractical technologies. What is clear is that a complex interplay of technical, social, and environmental factors has shaped the technology transfer and subsequent diffusion of these technologies. Using solar and nuclear energy as examples, the goal of this project is to evaluate and contrast the factors that are responsible for the introduction of these technologies, and to recommend international assistance and national level renewable energy dissemination and outreach policy.

Results to Date:

1. The discussions of the pros and cons of nuclear energy over the last 20 years are very instructive, but are not models of logical argument. On the one hand, nuclear power proponents argue that it is safe, can be economic, and that environmentally it is a good way for society to generate its electricity, and on the other opponents argue that it is inherently unsafe, uneconomic, and environmentally bad (Wilson 1994).

Our approach is not to argue the pros and cons in a standard technical manner. We discuss what we have noticed seem to be public perceptions of nuclear energy, and perceptions that have lasted long enough to be difficult to change or remove. We suggest that perceptions deeply enough held, cannot be changed easily even if wrong; and we suggest that they be regarded as constraints and that ways be found (albeit at some expense) to make the perceptions moot.

Constraints limiting the expansion of nuclear energy use particularly in the USA can be classified as safety concerns (both technical and health), economic, and political factors.

i) Technical: it is impossible to ensure absolute safety; large accidents can be disastrous; problems with waste disposal.

ii) Economic: construction time and costs; only large units are efficient; for safety reasons plants must be located far from large cities and cannot provide residential hot water (this is particularly important for Russia).

iii) Health: radiation exposure of workers and population.

iv) Domestic political concerns: lack of expertise; dependence on foreign technology and imports of enriched uranium creates elite groups of scientists and engineers.

v) International concerns: nuclear proliferation; terrorism; nuclear power produces only electricity (about 1/4 of total energy) and will have little impact on the total CO2 emissions anyway.

At present we are analyzing to what extent are these issues universal and to what extent are they held by one country alone.

2. The dissemination of small scale (typically 0 - 3 kW) solar photovoltaic (PV) systems in East Africa presents a remarkable range of accomplishments and pitfalls. In Kenya 10 - 20,000 PV systems have been installed through the efforts of commercial companies, private investors, and international assistance organizations. These facilities can be found throughout the country, on private farms, in rural hotels, health centers (frequently to operate medical refrigerators), and on office/apartment buildings. By contrast, the government of neighboring Tanzania has invested similar (minimal) funds in PV with results an order of magnitude poorer than Kenya, at best.

At present Richard Acker, a recent M. P. A from Princeton and a student of Professor Kammen, is conducting a survey of a sample of the PV installations in Kenya. The data spans technical aspects of the project (installation, operation and maintenance costs, the availability of materials and expertise), social issues (access to the generated power, relations with the purchaser or donor group, and resulting changes in livelihoods in the community or private business/residence), and environmental impacts (changes in fuelwood, kerosene, oil, and electricity consumption as well as perceptible local environmental changes such as reduced exposure to woodsmoke, deforestation, or pollution from combustion). The final database derived from the questionnaires will include one or more evaluations of 50 - 100 separate installations.

While preliminary, the results of this comparative study suggests a number of results with direct policy implications for further introduction of decentralized renewable energy technologies:

Projects are most likely to succeed when:

(i) expenditure on local infrastructure exceeds one- third of total funding;

(ii) expenditure on local technical training exceeds one- quarter of total funding;

(iii) a pre- existing local institution is charged and provided resources to maintain the facility, as opposed to initiating a new managerial infrastructure;

(iv) follow- up support continues for more than three years;

(v) emphasis is extended beyond, but includes, the household sector.

It is remarkable that all items (i - iv) identified are not generally part of project planning and the provision of resources by international lending and development agencies. A number of additional recommendations for development policy are under analysis, the most basic of which is the need for international lending to be reformed to smaller grant sizes distributed over longer durations.

The results of this work are in preparation for publication as a Princeton University Center for Energy and Environmental Studies (PU/CEES) report, and for submission to the international journal Energy Policy. The results of our analysis of the credibility of the U.S. energy projections performed during the first year of this project are now published (Shlyakhter et al. 1994).

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Implications for Environmental Policy

Many of the implications for environmental policy that can be drawn from this technology dissemination research follow from the recommendations for the reform of the development process. In particular we note that if 10 - 20,000 PV installations can be put into operation in Kenya, where generally inefficient woodfuel combustion is the norm (70% of the total national energy supply is derived from wood), significant reductions in greenhouse gas (primarily CO2, CH4, and N2O) emissions are possible.

Kenya's greenhouse gas emissions from industrial activities are profiled for 1988 in Table 1. The impact of non- CO2 trace gases emitted in Kenya on the global environment is more than three times that of CO2 alone. This highlights the importance of decentralized PV applications in developing nations such as Kenya. Not only does the installation of autonomous PV stations reduce the need for an expansion of the national grid - - and hence large transmission losses - - but it also reduced the need to burn fuelwood, which emits 1 0 - 50 times the greenhouse gases per kW provided as do larger generating facilities that themselves are largely impractical in Kenya (Smith et al., 1993).

As this research progresses, we expect to be in a position to compare the economics of large centralized renewables such as nuclear and hydroelectric facilities with the small- scale renewables of PV and wind.

The table highlights the importance of PV applications in a developing nation such as Kenya which lacks an extensive national grid:

 		CO2	CO	CH4	N2O
		(kT C)	(kT C)	(kT)	(kT)
Kenya		1,636	784	69	3
x GWP		1	4.5	22	280
emissions	1,636	3,532	1,518	840

Table 1: The greenhouse gas emissions scenario for Kenya prior to the introduction of PV technology. GWP = Global Warming Potential, or the relative capacity of one molecule of X to trap IR heat relative to CO2 over a 20 year time horizon as calculated by the IPCC (1992). The data is derived from estimates by Subak et al. (1992). Note that the non- CO2 emissions from energy and industry in Kenya have three times the impact on global warming as does the CO2 alone. kT = 103 tons.

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Intergovernmental panel on climate change (1992) Supplement, Cambridge Univ. Press, Cambridge, UK.

Smith, K. R., Khalil, M. A. K., Rasmussen, R. A., Thorneloe, Manegdeg, F. and Apte, M. (1992) "Greenhouse gases from biomass and fossil fuel stoves in developing countries: a Manila pilot study" Chemosphere, 26., 479 -506.

Subak, S., Raskin, P. and Von Hippel, D. (1992) National greenhouse gas accounts: current anthropogenic sources and sinks (Stockholm Environmental Institute: Sweden).

Shlyakhter A.I., Kammen D.M., Broido C.L., and Wilson R. (1994) "Quantifying the credibility of energy projections from trends in past data: the U.S. Energy sector," Energy Policy, v.22, p.119-130.

Wilson R. (1994) "The potential for nuclear power," in Global Energy Strategies, J.C.White, ed., Plenum Press, NY, p. 27-45.

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