Net metering and the seven myths
The recent announcement by NSPI and the provincial minister of energy about
NSPI's net metering programme may have some Nova Scotians interested in
purchasing a renewable electrical-generation system and becoming a
customer-generator (that is, someone who is both a consumer and generator of
However, there are a number of myths circulating about the benefits of net
metering that any potential customer-generator should be aware:
- Net metering means protection against NSPI's power outages.
For this protection, the customer-generator's generation system must be able
to store some of the electricity for use during outages.
If the system does not have storage, any power outage will still affect the
- Anyone in Nova Scotia can install a generation system for net metering.
Even if all Nova Scotians could afford the equipment, the Electricity
Marketplace Governance Committee (EMGC) and the minister of energy have
restricted the province's net metering capacity to 0.5 percent of NSPI's
annual peak (EMGC Recommendation 57).
Since NSPI's annual peak is about 2,200 megawatts, the net metering capacity
has been limited to 11 megawatts.
This means that the total capacity of the equipment installed by
customer-generators in Nova Scotia cannot exceed 11 megawatts; for example,
there could be no more than 550 customer-generators using 20-kilowatt
- Net metering is good for the environment because it will cause NSPI to
Ideally, all customer-generators would be producing 11 megawatts of electricity
simultaneously, allowing NSPI to reduce generation from its most polluting
thermal power stations by a corresponding amount.
However, since most renewable electrical-generation systems produce varying
levels of electricity intermittently, it is unlikely that NSPI will be able to
reduce its output by anything like 11 megawatts.
As a result, the impact of net metering on the quantity of pollutants released
by NSPI will be negligible.
- Net metering means getting paid for any electricity generated.
Ideally this would be the case; however, the EMGC and the minister of energy
do not require NSPI to compensate a customer-generator for any excess
generation (occurring when a customer-generator's production exceeds their
demand) (EMGC Recommendation 58).
Anyone planning to net meter should be aware of their annual electricity
demand and ensure that the proposed equipment meets only their demand, as any
excess is "free" electricity for NSPI.
- Greenhouse gas emission credits are available for customer-generators.
Once again, the EMGC and the minister of energy have ensured that the benefits
flow to NSPI: NSPI claims all the customer-generator's emissions credits
(EMGC Recommendation 61).
Whether NSPI actually deserves these credits is another matter altogether,
as credits should only be granted when it can be demonstrated that the
renewable generation actually displaces a measurable amount of greenhouse
The single meter approach to net metering employed in Nova Scotia will not
permit an accurate indication of whether any of NSPI's emissions were actually
- Wind turbines should be used for net metering, since the minister of
energy has repeatedly said that Nova Scotia has one of the best wind regimes
What the minister fails to mention is that Nova Scotia's wind resource is not
uniform across the province, meaning that the volume of electricity produced
by a turbine depends upon its location.
A poorly sited wind turbine can mean considerably less power generated than
expected, requiring the customer-generator to purchase more electricity than
Furthermore, small turbines can be noisy, which can lead to sleepless nights
and potentially upset neighbours.
Although photovoltaic panels cost more than wind turbines, they are easier to
install, aren't prone to mechanical failure, and most panels can produce
electricity, even on cloudy days.
- Electricity can be sold to neighbours rather than simply net-metered to
Selling electricity to one's neighbours is not permitted in Nova Scotia; any
electricity that a customer-generator produces can be supplied only to NSPI.
Anyone wanting to help the environment, and who has the money to spend,
should make their house as energy efficient as possible before becoming a
There are four actions that should be taken to improve the energy efficiency
of a house.
First, decrease space-heating requirements through insulation upgrades and, if
possible, maximizing solar gains.
Second, decrease conventional energy requirements for domestic hot water; for
example, by pre-heating water before it enters the hot water tank using a
solar thermal system.
Third, reduce electrical demand by purchasing energy-efficient appliances.
Fourth, replace incandescent lighting with compact-fluorescent lighting.
If the desire to become your own utility still hasn't been quenched after
improving the energy efficiency of your house, consider getting off the grid
entirely or rewiring part of your house to use the self-generated electricity.
This will cost somewhat more in that storage (typically deep-cycle solar
batteries) will be required.
However, with your own storage, you will be protected from power outages.
If you're completely off the grid, you will make a difference to the
environment (and you might even qualify for those emissions credits).
For more information on net metering, visit lh.ece.dal.ca/environment.
Submitted to Chronicle-Herald 3 November 2005 - unpublished