Great article, Nick. Thanks!

With respect to wind energy, earlier today in another forum I was discussing ways Canadian utilities could add additional wind resources to their generation portfolios without adversely impacting system stability. I thought I might share my thoughts with you in the context of this discussion:

Beyond geographically dispersing wind generation, strengthening interconnections with neighbouring utilities and more closely coupling wind resources with hydroelectric storage, real time pricing and intelligent load management could potentially allow wind energy to satisfy an increasingly larger share of our electricity needs.

Here in Canada, virtually all utilities are winter peaking and, by happy coincidence, wind capacity is greatest during these cold winter months. On the east coast, annual wind capacity factors generally fall in the range of 30 to 40 per cent, whilst winter numbers come in at 40 to 50 per cent and above.

Larry Hughes et all have come up with a novel idea of combining wind energy with electric thermal storage (ETS) heaters. This approach offers two key benefits. One is that it has the potential to reduce system peak by shifting a portion of the residential and commercial heating loads to off-peak hours (these loads can be curtailed during peak times and available wind resources redirected to serve other needs). Secondly, with two-way intelligent controls, these thermal storage heaters can be recharged/topped up anytime surplus wind energy is available. With two-way communication, excess energy can be allocated on the basis of greatest need (i.e., provided to those storage heaters with the lowest state of charge) or, alternatively, auctioned off to the highest bidder, as determined by various price parameters set by each user. In either case, wind availability in large part shapes the heating load, so that supply and demand remain better matched at all times.

For more information on this, see:
http://dclh.electricalandcomputerengineering.dal.ca/enen/2006/IGEC2-137.pdf

To a somewhat lesser degree, electric water heaters could be tied to available wind. Again, with two-way communications and fuzzy logic controls, these loads can be actively managed with little or no impact to the end user. Within acceptable limits, water temperatures within these storage cylinders would be allowed to rise and fall in sympathy with available supplies; a tempering valve would help facilitate this and, at the same time, ensure proper safety. Periodically boosting storage temperatures above 60C might also help kill the legionella bacteria commonly found in these tanks.

Duel fuel furnaces and boilers are one more possibility. Oil is the dominant heating fuel in Atlantic Canada. Two-thirds of all homes in Nova Scotia are heated with oil and this number climbs to 4 out of 5 in the case of PEI. At this time, heating oil retails for $0.85 to $0.90 a litre; assuming 80 per cent conversion efficiency, the cost of oil heat is a little over $0.10 per kWh(e). Nova Scotia Power's standard domestic rate is $0.1067 per kWh and its off-peak ETS rate is $0.0534. Assuming similarly attractive rates are offered to duel fuel customers, excess wind energy could be used to displace fuel oil in homes equipped with duel fuel heating systems.

For summer peaking utilities, commercial ice storage cooling systems are an attractive option. So too residential a/c, water heater and clothes dryer load controllers.

Cheers,
Paul