Sustainability and policy - Climate Change: Biological and Human Aspects - page 469

(hence cheaper) fossil carbon technology. Here, one of the best proven incentives are
what are known as 'feed-in tariffs' whereby renewable energy producers are subsid-
ised with an enhanced payment for the electricity they generate for national grids.
The first feed-in tariff was created by President Carter in 1978 with the US National
Energy Act. By 2011 some 50 nations have feed-in tariffs.
For feed-in tariffs to be accepted by private generators it is important for private
financial investors to be assured that agreed feed-in tariffs will remain for those who
sign up to them and not removed in the future. (Although tariffs may at some stage
be closed to new entrants.) These tariffs can be paid for in a number of ways, but
principally these are taxation of energy users, taxation of fossil energy consumption
(carbon tax) or taxation of fossil fuel production, or a combination thereof. Feed-
in tariffs need not continue for new energy production investors once the renewable
technology has matured and can compete without them. For example, according to the
Renewable Energy Association (the trade body for UK renewable energy producers) in
their evidence to a 2011 House of Commons Energy and Climate Change Committee
Select Committee enquiry, in Britain in 2010 photovoltaic solar power seems to be
near this point.
There is a substantial body of literature as to the potential of various renewable
energy resources to be found. My previous review (Cowie, 1998a) and the renewable
potential for the year 2025 is in line with the proportions of total non-fossil energy
contributions from a number of the IPCC (2000) scenarios including the principal
scenarios within its A1, A2, B1 and B2 groups. One reason for this is that the various
IPCC scenarios see their greatest divergence in emissions after 2025 through to 2100.
Another reason is that the most economically attractive sites that lend themselves to
renewable energy will be exploited first, which means that there is greater uncertainty
associated with estimates further into the future. Finally, because bulk exploitation of
renewable energy other than HEP is still in its infancy there is uncertainty associated
with these technologies. Broad working upper and lower estimates for potential non-
fossil renewables for the year 2025, should there be a drive to increase renewable
energies, are depicted in Table 8.2. These also straddle the International Energy
Agency's (2004) renewable potential forecast for 2030. The low estimate of 1296
mtoe roughly equates with a little over 1 GtC year − 1 whereas the high estimate of
1960 mtoe equates with around 1.7 GtC year − 1 . (For comparison, in 2000 some 8
GtC was released globally from fossil fuel.)
8.2.4 Prospectsforcarbon-capturetechnology
Improving energy efficiency is one way to increase the economic effectiveness of
fossil energy resources without increasing fossil consumption and developing renew-
able energy is another. However, as indicated in the previous sections, both these ways
have their limitations in contributing to a low-fossil energy strategy. With enough coal
for over two centuries of global consumption the question arises of whether there is
a way of continuing to use fossil carbon energy sources yet reduce carbon emissions
to the atmosphere. The comparatively new idea of carbon capture and storage (CCS)
has recently come to the fore.