This paper will be presented in Three Parts – this is the first portion that presents the background from which we begin…


Electricity is a convenient means of delivering energy to customers. The energy can be from any of a number of sources and electricity is simply the delivery mechanism to get energy from the source to users in a convenient and relatively efficient way. The most common sources of energy for making electricity are coal, hydro, nuclear and natural gas. Most of the new renewable sources (small hydro, wind & solar PV) use the electrical network for delivery. As we advance, the number of sources of “dirty fuel” on the network will decrease. For an average user, the only easy way to use a renewable energy source is to use electricity.

People generally have three means of getting most of the energy that they use. Fossil fuels are delivered either as a gas (natural gas) or as a liquid (petroleum products for vehicle transport) and electricity is delivered on the electricity grid.
As we reduce our carbon footprint, we will need to reduce the use of fossil fuels dramatically as these are the principle source of GHG emissions. For most people, this will mean reduced use of petroleum products including natural gas and automotive fuels, and an increase in both renewable energy and possibly nuclear energy. Hydrogen may fill a growing part of the mix and conservation will play an important role in the overall use of energy. The predominant delivery means is expected to be the electrical grid.

The grid is a mesh network of wire and cable that connects almost every home and factory to a large number of generating stations that are designed to convert a primary energy source into electricity. The grid has been designed with a few key issues in mind. It needs to be both cost effective and reliable. Reliability has played a large role in planning. A criterion referred to as N-1 is applied to almost all major transmission. Under any reasonable load situation, including the annual peak load, the loss of any single transmission component would not create a major failure. This criterion has resulted in a very reliable system under almost all circumstances, but it is requires significant redundancy. The criterion is very similar to the criteria that are used in the design of modern commercial aircraft. No single failure, other than perhaps a major structural failure is catastrophic. The loss of a single engine on any 2 or 4 engine aircraft can be tolerated, even during take off or landing.

The real problem with our electrical grid, is that on average it uses only 40-60% of its designed capacity, and often uses much less than that for short periods. The public has learned to live in a society where one can turn on a light, or an air conditioner at will, and expect the supply to be ready and available at all times. In northern locations, the annual peak, driven by heating loads, tends to occur on a dark cold night, usually close to Christmas. In warmer climates, the annual peak occurs on a very hot and humid afternoon, near the dinner hour, after days of similar weather. The grid has been designed and maintained to withstand single contingency failures at peak capacity; the rest of the time, it runs at far below capacity. Very few private companies could exist, knowing that they had invested billions on a system that ran at an average 60% capacity factor or less.

The term “Smart Grid” has been used extensively, and there seems to be little real detail beyond concepts of what a smart grid really is. To some, it means “smart meters” that tell people what they are using at the moment, and what they are paying. Time of use metering comes with this approach, and this is potentially a great opportunity to use pricing incentives to get the customers to shift some energy consuming tasks to off peak periods. One of the real problems with this approach, however, is the fact that only electricity is considered in the mix. No one pays much attention to the use of fossil fuel – the natural gas that comes in the pipe and typically provides the heat for space and domestic hot water.
Many of the initiatives that are popular these days – replacing lights with compact fluorescent lamp or turning off the computer when not in use are terrific means of reducing electricity use. These activities do more than reduce electricity use, because all electricity use ultimately turns to heat (unless it is used to charge a battery that is taken and used elsewhere). In summer, saving energy on lights or computers also reduces the need for air conditioning, resulting in a higher than expected saving in electricity. On the other hand, studies now show that these activities in a home that is heated in winter generally result in shifting the load from electricity to natural gas, because the heat that is removed by conserving electricity is simply replaced by burning more natural gas. In places where the electricity is generated from hydro, renewables, or even nuclear energy, this change can increase the GHG footprint of the user by a significant amount – a sad result for someone that was intending to do quite the opposite.

The electric grid in North America is a curious mix of energy sources. In Canada, about 60% of all electricity comes from hydropower, a clean source. A further 18% is generated in nuclear plants, another source that emits little or no GHG from operations. An important and growing sector is wind, solar, and other renewable energy sources. Burning fossil fuel generates most of the remainder. The situation in the US is quite different. Almost 50% of the total generation is the result of burning coal, about 18% is from burning natural gas, and from that base, it gets cleaner. A total of 17% comes from nuclear energy and most of the balance is renewable, including hydro. Canada’s electricity is currently much cleaner than the electricity generated in the US.

Next… constraints on supply that shape the fuels that are selected to provide our electricity…