Science

Nuclear, renewables best power-generation blend: Experts

Despite recent events in Japan, some maintain that New Brunswick's proposal to blend renewable and nuclear power is the way the modern electrical grid should be developed.
The proposed plan for New Brunswick's clean energy park put nuclear power front and centre, surrounded by renewable energy sources.

New Brunswick's bold idea for a "clean energy park" is mired in red tape and delays, and the nuclear disaster in Japan has raised new questions about the use of atomic energy. But some maintain that the province's idea to blend renewable and nuclear power is the way the modern electrical grid should be developed.

In July 2010, the province of New Brunswick and NB Power signed a letter of intent with French reactor-maker Areva to establish the park alongside the Point Lepreau Nuclear Generating Station. At the heart of the park would be a brand new, Generation III+ nuclear plant, integrated with a variety of renewable energy sources, including near-shore and offshore wind and biomass.

The refurbishment of Point Lepreau, Atlantic Canada's only nuclear reactor, is three years behind its original schedule. (CBC)
Even up to February of 2011, the park was reported to be under discussion as Areva and Mitsubishi Heavy Industries Ltd. (MHI) submitted the ATMEA1 reactor for pre-project design review. This would have been the first light water, non-CANDU reactor installation in Canada.

In recent weeks, a change of government and a severely delayed refurbishment project at Point Lepreau, along with the reactor disaster in Japan, have combined to put the clean energy park in limbo. As one spokesperson from the Department of Energy put it, "There's no commitment, but we've not ripped up the memorandum of understanding."

However, the spirit of the park is something that serves as a model for where some believe nuclear should fit into the renewable energy picture in the coming years. And much like the mockups of the park's own plan, nuclear is a big part of the overall picture when it comes to strategies that replace fossil-fuel-based generation with renewable sources.

Base-building

In large part, that's because in regions where nuclear power plants exists, there are those who will argue it is one of the more reliable and cost-effective sources of baseload power.

As Denise Carpenter, president and CEO of the Canadian Nuclear Association in Ottawa, explains, "It's pretty simple. Baseload is when a facility can produce a lot of power 24/7 for a long period of time. Think of it as the bottom of a pyramid. You can then stack renewables on top of that."

In a carbon-conscious world, a reliable baseload can support the development of renewables such as solar, wind or biomass. In Canada especially, the abundance of hydro — which also serves as a major baseload resource in areas such as Quebec — means that nuclear and hydro still rank among the most cost-efficient options for generating the amount of power needed to meet growing electricity demand.

Power in Canada

Canada's energy demand is expected to increase by 34 per cent by 2025, creating higher requirement for reliable, clean electricity.

  • The Government of Canada has set the objective that 90 per cent of Canada's electricity needs be provided by non-emitting sources such as hydro, nuclear, clean coal or wind power by 2020.
  • In 2009, electricity in Ontario was generated from nuclear (55.2 per cent), hydro (25.5 per cent), natural gas (10.3 per cent), coal (6.6 per cent), wind (1.6 per cent) and other alternative sources (0.8 per cent) (Source: IESO - Independent Electricity System Operator).
  • By 2020, Ontario will need to replace about 80 per cent of its electricity generation (25,000 MW) because of growth in demand and aging plants.
  • Bruce Power is refurbishing Bruce A (ON) Units 1 & 2 (805 MW each) with a return to service date in 2011 and will refurbish Bruce A Units 3 & 4 upon completion of 1 & 2.
  • The top two performing nuclear reactors in Ontario in 2009 were Bruce 5 (872 MW) which was generating power 95.4 per cent of the year, and Pickering 7 (540 MW) at 94.3 per cent.
  • Québec has only one nuclear power station in operation: Gentilly-2, owned by Hydro-Québec which came into commercial operation in 1983 and now supplies 3 per cent of the energy in the Hydro-Québec grid. It is now being refurbished.
  • Point Lepreau Generation Station is Atlantic Canada's only nuclear facility and began generating nuclear power commercially in February 1983. It was the first CANDU 6 in the world to be licensed for operation and now provides up to 30 per cent of the New Brunswick's electricity.
  • On April 1, 2008 NB Power began refurbishment of Point Lepreau to extend the station's life to 2032.

(Source: Canadian Nuclear Association Fact Book)

The main reasons that renewables such as wind and solar still represent a small portion of the energy picture range from real estate, storage limitations and cost, to productivity issues and the vagaries of Mother Nature. For example, an average wind turbine runs at around 30 per cent efficiency over the course of a year because of the amount of time that the wind doesn't blow hard enough to generate power, while a well-maintained nuclear generator can run at up to 95 per cent efficiency, according to Tom Adams, a Toronto-based energy consultant.

In real terms, this is how those numbers stack up. "Look at Darlington, for example, which is operating at 85 per cent productivity ratios," Adams explains. "For wind, those ratios are around the high 20s to low 30s. To generate the same kilowatt hours [ver a given period of time], therefore, you need 3 megawatts of wind for every 1MW from nuclear. Given that Darlington produces over 3,500MW, you would need close to triple the number of wind turbines to match that."

However, when talking baseload and renewables, it's the combination of technologies that you bring to the mix that works to supply the grid with a regular flow of power.

"Some renewables are very compatible with nuclear," Adams said. "That's because nuclear is not good at fluctuating output to meet changing electricity patterns. Neither is wind or solar. Hydro electric can."

A good renewable strategy can be a matter of striking the right balance, he adds.

"Nuclear and hydro are good partners," Adams said. "But nuclear, wind and solar can be a mismatch [depending on the ratios]. Hydro, wind and solar are a good match."

Tough Times Ahead

Nuclear supplied 55 per cent of the energy requirements in 2010 in Ontario, Adams adds. For the time being, renewable energy sources such as wind and solar comprise well under 5 per cent.

Point Lepreau Nuclear Generating Station in New Brunswick is being strengthened against possible earthquakes. (CBC) (CBC)
But those ratios will change. Adams reports that last year wind contributed 1.9 per cent to Ontario's energy picture. It's expected to double this year, and is projected to hit 5 per cent very shortly.

Understandably, however, nuclear is also coming under a lot of scrutiny in light of recent events in Japan.

However, John Herron, president of the Centre for Atlantica Energy, a "meeting ground" for government, industry, community and academia in Saint John, NB, believes that the effect on nuclear programs will be relatively short-term. "Japan will create a pause in some enthusiasm for nuclear on this continent, but I don't think this will cause long-term problems."

The truth of the matter is, business needs prevail when it comes to setting power generation policies, and businesses need affordable electricity.

"The cost competitiveness of any region relies on how cost-competitive its energy is," Herron said. "A region has to have competitively-priced energy to attractive industrial development.  B.C.'s renewable energy strategy for example says yes to renewables, but not to the detriment of driving up energy costs."

While nuclear may be expensive to ramp up or down, "It's measurably cheaper to run for baseload," Herron said. "Even when a refurbishment like Lepreau has gone poorly and costs have escalated, the business case for nuclear is still there. If someone says for $2.5 billion you could get 700MW of generating capacity for 25 years, you would still say yes in a heartbeat."

Holding Power

As long as the insatiable demand for electricity continues, nuclear will have its place, because electricity demand mirrors economic growth, says Jean-Francois Beland, executive vice-president for Areva Canada in Pickering, Ont. "A plan for nuclear baseload generation capacity, combined with peak capacity of wind or biomass, is a strong combination in energy provision."

"As we move to a carbon-constrained world, you need to have a mix of fuel sources," Carpenter added. "Every region is different and each has a role to play. As we see more need for electricity, we also see bigger requirements for non-emitting baseloads. For Quebec, hydro is its non-emitting baseload. Nuclear is a zero emission option for Ontario and New Brunswick. If it doesn't grow, if nothing else, it will stay at about 50 per cent [in Ontario] for now."

Herron agrees that nuclear should remain a part of a balanced energy portfolio. "That's because scale does matter. The source of energy matters — i.e. no coal, no oil. Wind is coming in at price points that kind of works for homes. Solar adoption is comparatively low. Tidal power is not ready yet. Nuclear is a good purchase decision for the capacity you get for the length of time it produces [energy]."

The longevity and reliability of nuclear as a baseload continues to offer ongoing opportunities for building on a renewable energy strategy, confirms Ted Gruetzner, a spokesperson for Ontario Power Generation in Toronto. "Nuclear is an enabler of renewables because you have to have backup. There's a real value in having a balanced mix of energy sources."