While we’re making observations in Australia, here’s another one from The Conversation, the blog of Mike Sandiford – Director, Melbourne Energy Institute at University of Melbourne. It’s a helpful reminder that while it’s easy to be pessimistic about the prospect of the political class addressing climate change, it’s also too easy to discount the effect that the application of technology can have.
Here’s an example, which though technical, shows how incremental change can deflect the upward slopes of trends which would otherwise take us to a bad place.
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Since the last hot summer in 2010, our electricity system has seen a lot of changes. For one thing, almost 2 gigawatts of distributed generation has been added in the form of domestic solar PV. To put that in context, 2 gigawatts represents a touch under 10% of average summer demand, though of course solar PV only produces at near maximum levels for a few hours in the middle of a sunny summer day. However, when solar PV is producing it takes away from the demand for electricity that otherwise would be dispatched across the poles and wires via our National Electricity Market – or NEM.
So with this summer just past setting new records for extreme heat, it’s a good time to point the summer sun on the NEM and see how it is standing up.
With blistering summer heat, particularly across New South Wales and Queensland, there was an expectation we might see new records in peak demand. But despite the weather and the supposed new air-conditioning load, the NEM doesn’t seem to have been pushed very hard at all during this last summer.
In Queensland peak demand was the lowest in 5 years, down 360 megawatts on 2012 levels.
Average (left) and peak (right) QLD demand, for Summer months (Dec, Jan, Feb) Data from AEMO, image by Mike Sandiford.
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In New South Wales peak demand was up a massive 1.6 gigawatts from the previous summer but that was no great achievement, since the 2012 peak was the lowest since 2002. In fact the New South Wales peak this summer was almost 700 megawatts below 2011, and came in at only the third highest on record.
Average (left) and peak (right) NSW Summer months (Dec, Jan, Feb) demand Data from AEMO, image by Mike Sandiford.
… Up until about 2008, peak demand was growing at around 3% each year. So back then the expectation was for peak demand to rise another 15% or so by 2013. In Victoria that meant planning for a 2013 peak demand of around 12 gigawatts, some 25% higher than we actually achieved. …
One obvious contributor to the general decline in demand for electricity dispatch by the NEM, and the lack of extreme peaks, is solar PV (photovoltaic). …
Because solar PV capacity has been ramped up so quickly, the way it is impacting is readily assessed by comparing this summer daily average demand profile to that of a few years ago. When we do so, the signal of solar PV becomes blindingly obvious, especially in South Australia and Queensland where the domestic solar PV penetration is highest.
… solar PV is impacting by cutting more than 10% off midday summer demand in South Australia compared with the summer of 2010. It is also skewing the average demand profile, making it more peaky in the late afternoon, as air-conditioning adds load while PV diminishes in output. It is also clear that solar PV has helped shave some of the peak load, which up until a few years ago was occurring at around 3 pm, and is now pushed back to lower levels, later in the afternoon.
… It’s salient to ask what would happen to electricity demand if solar PV penetration reached 50% of houses. What it would do, as indicated in the Figure below, is take midday demand down to near the lowest in the 24-hour cycle, effectively creating a second off-peak demand regime.
Projected average summer demand profile by time of day for SA, consistent with a doubling of PV installations out to 2016. The left panel shows absolute demand. The right panel shows the percentage change relative to the summer of 2010.
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Way more detail here.
Yes, solar voltaic makes total sense in hot sunny climates like Australia, southern US, Hawaii, Alberta or even Okanagan, BC or Ontario as it produces the most electricity when A/C demand is highest, ie hot afternoons. That is why they are so common in S-Europe, Australia or Hawaii where electricity costs are very high. Not so common in BC yet as hydro generated electricity is so cheap. The Ontario government instituted such changes mistakenly forcing solar onto the grid at 80 cents a kw/h now 40-60 cents far above current hydro or nucleo rates. This left Ontario taxpayers on the hook for massive energy price hikes and higher debt. Similarly in Spain and Australia where both governments have now cancelled those massive job-destroying and debt-creating subsidies.
No one doubts the benefits of solar technology where it makes sense. The question is: should governments use tax payer money on a large scale to force it ? To me the answer is a clear no, but of course to many it is yes.
Yes to solar, no to government intervention creating more debt and killing jobs due to higher energy costs !
A few points in rebuttal:
1) “no to government intervention creating more debt”? You mean, like the decade-old government intervention to keep BC Hydro rates artificially low? Leading to a ballooning BC Hydro debt load of $5 billion?
http://www.theglobeandmail.com/news/british-columbia/double-digit-rate-hikes-still-loom-for-bc-hydro/article15599460/
2) You may not be aware of this, but Vancouver has a pretty sunny summertime climate as well. Vancouver’s westside homes have sprouted A/C systems over the past decade, and our downtown offices and condo towers have pretty heavy A/C cooling loads in the summer. This is largely thanks to all that glass-happy curtain wall construction. On the spot market, hourly electricity rates on hot summer days can spike from the usual $0.04-0.08/kWh, to well over $0.35-0.45/kWh. As pointed out in the article that Gordon linked to, this is exactly when solar PV does its most effective job of providing electricity to the grid.
3) In Vancouver, we have the Burrard Generating Station. A 950 MW natural gas powered relic from the 1960s that provides us with “emergency” back-up power. For the past 5 years, it has been used roughly 1% of the time (on an annual basis), for these types of extremely hot days. There’s long been talk of mothballing it, and bringing in power from other natural gas plants elsewhere in BC to handle these spikes in demand, but this would require new transmission line capacity, at a cost of multiple millions (not to mention the environmental impact of running new transmission lines). It would be an interesting exercise for a university student to compare the costs of installing new solar PV capacity in Metro Vancouver, versus what BC Hydro is contemplating (with the usual political meddling from the province).
4) Solar PV rates have dropped dramatically over the past 4 years, to the point where a recent Deutsche Bank analyst report mentioned that solar PV can provide electricity for less than market rates in 19 markets worldwide (including Spain, Germany, Italy, Turkey, Chile, Argentina, most southern US states, Japan, Greece, and China). The city of Austin, Texas, recently signed a 20 year Power Purchase Agreement for $0.05/kWh. Even with our less-sunny climate (our insolation rates are roughly 55% of Austin’s), we should be able to see Industrial-sized solar PV systems provide electricity at around $0.11/kWh, and residential-sized systems at around $0.20/kWh.
I’ll end on this optimistic note. Germany covered 74% of its total electricity needs with power from renewable sources (wind, solar, biomass) on May 11th of this year, on a day when half the country was shrouded in clouds and rain:
http://www.greentechmedia.com/articles/read/Renewables-Surged-to-74-of-German-Demand-Last-Sunday
This was only possible thanks to a very effective government law that supported solar, wind and biomass installations.
The same trend that you note in Australia is also is occurring in California, as very large amounts of new solar generation have started feeding electricity into the grid. There too, what was a broad daytime peak period is rapidly becoming a low net demand period, once renewable energy generation is subtracted from load.
http://www.caiso.com/market/Pages/ReportsBulletins/DailyRenewablesWatch.aspx
In California, they refer to the “Duck Curve” – a comparison of the total demand curve over the day, and the net load after renewable energy generation is subtracted, since the two curves on the same graph look like, well, a duck. http://www.caiso.com/Documents/FlexibleResourcesHelpRenewables_FastFacts.pdf
You’ll note that California’s considerable wind energy production tends to happen at night, while the solar energy produces during the day – a good tag-team of renewable energies. Other renewables contribute at lower levels with a base-load profile – also very useful.
In BC, wind energy production from the Peace Region and the coast (the areas where BC has operating wind farms) is consistent over the day and night. As a result, the more wind farms are in operation, the more the combined output of these wind farms will approximate constant base-load supply. This is a very useful advantage we have here in BC.
And while BC wind energy resources provide consistent power over the day and night, they also produce much more energy during the winter, when our domestic demand is highest (with heating and lighting loads), and our hydro production is most constrained. During the spring freshet period, when domestic demand is at its lowest (long sunny days and low heating requirements) and our large and small hydro plants are producing at maximum, BC’s wind energy production is at its lowest, a happy synergy. It doesn’t work this way everywhere, but in BC, aggregated wind energy resources can provide provide us with large amounts of consistent power day and night when we need it in the fall through spring, with tapered production during freshet when we already have adequate supply with our hydro resources.