Al Gore must be nitrogen’s atomic enemy No. 1. Making up almost 80% of the air we breath, nitrogen receives little attention in comparison to carbon dioxide these days. Carbon footprint, carbon neutral, carbon offset, carbon sequestration, carbon trading have quickly been integrated into the lexicon of modern-day life. Increased environmental awareness has prompted many individuals and nations to reconsider the potential impact of everyday activities on the climate of tomorrow.

The electricity industry has understandably become a target of these concerns. Preliminary data suggests that power generation was responsible for 42% of the 5890 million metric tonnes of CO2 emitted in the USA in 2006 . In Canada, power generation was responsible for approximately 43% of all reported emissions for that same year . In light of these figures, renewable energy alternatives have quickly been gaining favour among regulators.

Renewable Portfolio Standards (RPS) have been established at the state-level while federal regulators edge closer to legislation implementing renewable energy across the nation. According to US Department of Energy, 26 states have mandatory RPS obligations with an additional 3 states setting voluntary standards. These standards vary between jurisdictions, with California and New York setting aggressive targets of 20% and 23% by the years 2010 and 2013 respectively.

The green shift is occurring north of the border as well. The Ontario Power Authority is proposing almost doubling the province’s renewable energy by 2025 in so far that renewable power makes up 40% of the installed generation capacity. Canada’s smallest province, Prince Edward Island, is targeting to meet its electricity needs using 100% renewable energy by 2015, thus eliminating the need for imports from out-of-province. Even hydro-rich Quebec is integrating 4000MW of wind power by 2016.

The greening of the grid is an integral part of 21st century’s distribution system but a reduction in CO2 emissions is just one challenge facing system planners.  In the digital age, North American economies are increasingly dependent on a reliable power supply for sustained growth. Power outages have a tremendous impact on the economy. It is estimated that the US loses from $119 to $188 billion annually as a result of outages and power quality issues.  An hour long power outage at the Chicago Board of Trade in the summer of 2000 pre-empted approximately $20 trillion worth in trade. The Blackout of 2003, which cast the US Northeast and Ontario in darkness for up to two days, is estimated to have cost between $7 and $10 billion.

To ensure global competitiveness, the antiquated grid infrastructure must be updated to provide needed flexibility and reliability. As the technology and infrastructure facilitate the evolution of the Modern Grid or Smart Grid, large centralized generation will coexist with small-scale distributed energy sources such as a 25MW solar array or a 5MW wind farm. The centralized linear generate-supply-consume model followed essentially since Edison had his bright idea will need to be replaced with a dynamic, interactive model which allows all participants a role in balancing supply and demand. The Smart Grid is designed to accommodate the needs of the technological age. This emerging framework will:

1. Provide real-time system optimization allowing the capacity to detect, analyze and restore system faults at the local scale;


2. Motivate supply-side participation through consumer education and enabling technologies;


3. Be more resistant to attacks through increased physical and network security features;


4. Resolve power quality issues before manifestation;


5. Improve integration of small generators and increase the proportion of renewable energy sources in the supply mix;


6. Optimize assets and efficiencies to minimize the need to build new generation and supporting infrastructure; and


7. Enable markets through open-access systems that offer consumers choice and create efficiencies.

The Smart Grid is a Green Grid by promoting efficient use of electricity and increasing the role of renewable energy in supplying consumer demand. As a result, investments in renewable energy sources have increased significantly. The US Department of Energy’s Office of Energy Efficiency & Renewable Energy reported that global investments increased by 41% in 2007 reaching $117.2 billion. Almost half of that amount ($54.5 billion) was invested in wind power and this growth is likely to continue. Last summer, in the Renewable energy country attractiveness index, Ernst & Young predicted that investments in this sector could top $750 billion within 10 years. The United States was rated first in terms of attractiveness in all categories. Wind power has proven attractive to investors with a record 5021MW installed in 2007, bringing the nation-wide total to 16596MW of installed wind power spread across 34 states.

 At present wind, solar power and biomass make up only 2% of the installed generation capacity in the US, with hydro bringing the total renewable supply to 13% of overall capacity. Yet in terms of net consumption, renewables supply only 9% of the electricity used by US consumers. Coal power on the other hand accounts for 32% of installed capacity, but supplies 49% of overall US demand.  This apparent disparity underlines three critical challenges facing the widespread integration of renewable energy into the grid of the future, namely reliability, economics and location.

When the Wind Blows

Of the renewable alternatives in the supply mix, wind has proven most attractive to investors, yet there is often a large discrepancy between nameplate capacity and generation output. An industry standard suggests an efficiency value of 30%, indicating that a 1 MW turbine would likely generate on average 2628 MWh over a one year time period. The simple fact is that despite the use of wind forecasting to optimize wind power integration, the wind itself is variable and as such, presents various operational challenges .

1. Minimum Load: Times of high wind production may coincide with minimum load on the grid, requiring the system planners to reduce production from conventional power plants until supply and demand is restored. In some instances this may drop the spot price.


2. Ramping:  Variations in wind can ramp up and down ±10 percent of capacity much of the time over the hour. However, variations are most prominent when output is between 25% and 75%. The largest variations are when the wind output is storm driven, reaching maximum output and reducing output quickly when the storm has passed.

 Solar power faces similar challenges. Although the sun will always rise tomorrow, variations in output due to cloud cover and the changing seasons promote an efficiency statistic of approximately 30%. The reliability of hydro-electric resources has also been questioned. Although historically reliable, the threats of climate change and potential shifting hydrological patterns have created concern among system planners about hydro-electric resources in the coming years.

The Colour of Energy

Power on Demand could be the slogan of any system operator. Delivering electricity where and when it’s needed is the mandate of Independent System Operators across North America. But just how much are consumers willing to pay to clear the air? Nuclear and/or coal power resources make up the base load of many existing North American electricity markets due to economics. Coal is cheap and reasonably plentiful and can easily be dispatched as demand increases. Yet coal power generation is responsible for 59% of the sulphur dioxide and 19% of the nitrous oxide emitted annually  not to mention the carbon emissions. In an era increasingly dependent on electricity for economic sustainability, what price are consumers ready to pay for increased environmental sustainability?

While renewable energy has attracted much investment and federal, state and provincial governments have provided incentives to increase the percentage of renewable energy alternatives in the supply mix, this cost is ultimately going to be passed on to the consumer. How supply and demand will be balanced with increased prices for a resource seen as essential poses a challenge for market planners. Will a price for carbon offset the apparent price discrepancy between coal and renewables? If so, what criteria would be used to assign a value the carbon commodity? What impacts will such an action have on the economy and/or the environment?

A River Doesn’t Always Run Through It

The integration of renewable energy into the modern grid is complicated by the spatial diversity of resources. The implications of this are two-fold. Firstly, the uneven distribution of solar, wind or hydro-electric potential inhibits the implementation of a national RPS. The have-not states would be required to import renewable energy to comply with minimum requirements. Secondly, this would be initially impeded by the required upgrades in transmission and distribution infrastructure.

New infrastructure is imperative for the Modern Grid and the integration of renewable resources. Increased capacity and spatially-distributed generation assets require a dynamic, interactive communication network that provides the flexibility and efficiency in distributing electricity. A case in point would be unscheduled power flows as a result of high wind production and low demand. With insufficient North-South transmission lines, the combined wind output of Denmark and Germany results in the transmission from Northern to Southern Germany via the transmission networks of the Netherlands, Belgium and France.

These challenges are not insurmountable but will require a pragmatic approach to balancing the green equation; a reliable power supply that balances the renewables with existing power sources to reduce greenhouse gas emissions. A critical component of this equation will be consumer response. Modern Grid technologies will provide consumers the tools with which to participate and address their primary objectives, whether these are lowering electricity bills, enhancing productivity or reducing their environmental impact.

The consumer holds the key to ensuring the integration of renewables into the supply mix. Conservation & Demand Management initiatives are becoming more prevalent, giving consumers options. Energy efficiency and load management provide a ready resource and alternative to relying solely on the conventional power sources. Demand response resources serve to complement the intermittent nature of wind & solar power alternatives. Environmental concerns have fueled the growth in renewable energy alternatives over the past decade. Efficient use of resources will be the driving factor of the Modern Grid.

About the Author

Caroline Lofthouse is the Communications Specialist for Rodan Energy & Metering Solutions located in Mississauga, Ontario. As a Metering Services Provider licensed with the IESO, Rodan provides high voltage metering and power systems engineering services as well as a full suite of sub-metering, data management and settlement solutions. Under its EnerShift brand, Rodan has become the leading provider of demand response and energy efficiency aggregation services in Ontario. Caroline joined Rodan in 2006 upon completion of a M.Sc. from York University in Toronto, ON.