Imagine: a real alternative energy plan

Thursday, May 10, 2007

Climate change is a dire threat to human existence. Yet the plans to tackle it put forward by the Coalition and Labor fall far short of what is necessary. Politicians present as "common sense" that renewable energy can play only a peripheral role in Australia. However, Zane Alcorn explains the potential for a renewables-based transformation of Australia's electricity grid, beginning in 2008.

This hypothetical plan for virtually eliminating greenhouse gas emissions related to power generation assumes that massive productivity drives, such as wartime military manufacturing, could be emulated for the task of halting climate change. It focuses on energy generation, rather than other crucial areas such as transport, agriculture and the built-up environment.

To reduce carbon dioxide (CO2) emissions, the energy generation sector would have to be rapidly refitted. Twenty-four coal-fired power stations account for 50-55% of Australia's emissions, more than any other sector. BHP Billiton and Rio Tinto would have to be nationalised to start to phase out coal power and exports.

The economy would have to be reorganised democratically to implement a three-phase program to reduce emissions to near zero levels by 2020. During phase one, starting in 2008, several large solar photovoltaic and wind turbine factories and associated component factories would be set up. Some factories would be retooled to produce solar panels or turbine components. Locations for new windfarms would be sought with the input of community groups and wildlife authorities.

An expanded renewable energy division would be commissioned at the CSIRO to immediately fine-tune solar thermal technology for mass production, as well as to develop "hot dry rock" (HDR) geothermal technology for immediate use. Further development of wind, solar photovoltaics, biomass and biogas, thermal chimney, wave, tidal and other renewables would also be a top priority. The use of renewables would mean that the grid would need to be transformed to deal with less-centralised power generation. The CSIRO's renewables division would be empowered to build full-size prototype generators.

In 2010, several large new gas-fired power stations would be built, replacing existing coal-fired plants and providing flexible backup for the pending renewables network. Large wind farms would be linked into the grid; heavily subsidised photovoltaics would made available for workers' homes and be mandatory for large businesses and factories.

Biomass processing plants and distilleries would be built in all major cities and in rural centres where large amounts of agricultural waste is generated. They would extract methane, biodiesel, ethanol and combustible biomass and charcoal from fermented vegetable and agricultural waste products and manure. There would be a strong emphasis on using existing waste products to produce biofuels and
biomass, rather than growing crops explicitly for these purposes.

Biogas-harvesting sewage treatment plants would also be built, with treated sewage irrigating large hemp plantations. The hemp could be used for textiles, building products and biomass, while the biogas (methane) harvested from the sewage and biomass plants could be fed into gas-fired power stations.

Phase one would be completed by around 2014, and would supply 20% of Australia's baseload requirements with wind power (and up to 35% during production peaks) and would supply around 10% of daytime baseload requirements with solar photovoltaic power.

This first wave of renewables would be backed by gas power plants providing up to 25% of baseload requirements, and would allow about a third of Australia's coal-fired power stations to be permanently phased out. Victoria's Latrobe Valley brown-coal-fired power stations, and the oldest and least efficient coal plants in NSW, would be among the first plants to be retired.

During phase two, 2014-17, solar thermal concentrating plants with molten-salt heat storage would provide a further 10% of baseload requirements. Another 10% of baseload power would be supplied by HDR geothermal plants.

Another 5% of baseload would be provided by new gas plants, and 5% by a further rollout of solar photovoltaics. Biomass plants (either new or reconditioned coal plants) would provide a further 10% of baseload requirements. Windfarms providing a 2% average baseload would be built.

Smart meters would be installed in homes, offices and factories to allow individual units such as air conditioners to be switched on or off by a centralised grid regulator en-masse to shed power load during peaks in electricity use (currently, since smart meters are not in use, whole suburbs occasionally need to be shut down during demand peaks such as heat waves). During this second phase, half of the remaining coal-fired power stations would be phased out. By now, the wind turbine and solar panel factories would be producing a substantial surplus of panels and turbines that could be traded internationally, allowing a major scaling back of coal exports.

Phase three, 2017-20, would rely in part on the CSIRO renewables division refining more experimental technologies (but not "clean coal"). Solar chimney plants would be built providing 3% of baseload requirements. Wave plants will account for an average 2% of capacity, and tidal plants for another 2%.

Solar thermal plants with molten-salt heat storage would be built to provide another 7% of baseload requirements, another 2% of baseload would be provided by wind, and a further 5% of peak daytime power would be supplied by a third rollout of solar panels. Biomass, either through new plants or reconditioned coal plants, would provide another 7%; HDR geothermal would provide another 5%. A further 5% of gas-fired baseload would also be built.

At this point, Australia would essentially have a zero-emission power grid and would be in a position to phase out remaining coal-fired power stations (perhaps a plant could be retained for nostalgic reasons, and run mainly on biomass).

This plan, based on percentages rather than wattages, is designed to emphasise that the geographic opportunities for wind, concentrating solar thermal, solar photovoltaic and geothermal are the determining factors in the mix, not the size of the grid.

If Australia's new baseload capacity is about the same as it is now, existing hydro electricity would provide about 9% of the new grid's requirements. Together with the installed gas, geothermal and biomass plants this segment of the grid would provide up to 74% of peak baseload capacity whenever required.

The gas and hydro sectors (and, to a lesser extent, the biomass) can also be quickly and easily ramped down and shut off, meaning that for much of the year (and especially during the day when the solar thermal plants and solar panels are at maximum output), the grid can be running on 100% green renewable energy.

The 17% of the grid supplied by solar thermal power may drop back to 8% at night when the molten-salt backup is running, and the 3% thermal chimney may drop back to 2% at night. Nonetheless another 10% of round-the-clock power could
be provided, taking the 24-hour reliable baseload total to 84%. The wave and tidal power units may contribute a small percentage more to the round-the-clock baseload available.

In summer, 20% of baseload could be supplied through the hottest part of the day by solar photovoltaic panels. The beauty of solar panels (and solar thermal plants) is that they produce the most power when air-conditioner-use peaks.

This leaves wind power, which has an installed peak capacity of over half of the grid's requirements. While it would almost never produce anywhere near its full capacity, it could certainly be built to quite reliably provide nearly a quarter of baseload needs around the clock.

Sometimes the wind farms would produce tremendous amounts of energy 30-40% of national grid requirements at which point the gas and biomass plants would be ramped down.

A large portion of essential water and sewage pumping could be pumped off peak using wind power. Similarly, water could be pumped into hydro electric dams to be recycled during periods of peak demand. Desalination plants and hydrogen-producing electrolysis plants could be built specifically to soak up peaks in wind energy production; the water has obvious uses and the hydrogen can be blended with natural gas to run the gas-fired power stations and gas-powered vehicles.

The gas plants could run on a cleaner blend of regular natural gas with 25% biogas and 15% hydrogen, resulting in lower particulate emissions and around a third less net CO2 emissions than straight natural gas.

Initially there may be some power shortages. This may mean keeping one or two coal stations running while another couple of gas-fired plants are built.

Perhaps the CSIRO renewables division would not be able to deliver the full targets of solar thermal, geothermal wave or tidal power by 2020. But it could also perhaps exceed the targets. Either way, based on working examples of large-scale wind, geothermal, solar thermal, solar photovoltaic and biomass plants around the world, one can safely assert that building a national grid to consistently and reliably run on more than 70% (and at times up to 100%) renewables is already, today, practical.

Building a near zero emissions power station network would cost somewhere between $50-$120 billion and would create a renewables exports stream worth $5-$10 billion per annum. The plan would employ upwards of 150,000 people, massively outstrip the export potential of the uranium and coal industries and in providing a vast amount of safe, quality jobs. Australia would become an authorative voice in the global emissions reduction drive, and would be able to assist developing countries' transition to renewables.

However, the restructuring of the grid is a massive investment and would only return profits over a long period. Such a plan will never emerge from the private sector, which demands quick, 5-10 year returns on investments. Halting climate change is a social investment, not a money-spinner.

The arsenal for the war on climate change already exists. But a renewables revolution can only happen if coal-addicted corporate Australia is removed from holding political and economic power.

[Zane Alcorn is a member of Resistance, an affiliate of the Socialist Alliance. A longer version of this article is available in the Socialist Alliance's internal discussion bulletin.]