Category Archives: Uncategorized

Lower and Lower Energy Prices from Wind and Solar PV

Reduction in installed costs and operation costs (per kW or MW – see http://benoit.marcoux.ca/blog/the-costs-of-wind-and-solar-pv-systems-are-down-way-down/), coupled with free “fuel” converted into electricity at increasing efficiency, translate directly into lower and lower cost of energy (kWh or MWh). The dropping cost of wind and solar energy can be followed in 2 ways. First, analysts compute the costs over the expected life of a plant, estimate energy production and allocate a fair return for owners to come up with the Levelized Cost Of Energy (LCOE). Second, real-life auctions leading to long-term Power Purchase Agreements (PPA) from utility-scale plants provide actual price data.

At the global level, the International Renewable Energy Agency (IRENA) has built a Renewable Cost Database containing the project level details for almost 15,000 utility-scale renewable power generation projects around the world, from large GW-scale hydropower projects to small solar PV projects, down to 1 MW. IRENA also has an Auctions Database which tracks the results of competitive procurement of renewable power generation capacity that are in the public domain. The Auctions Database currently contains auction results for around 7,000 projects, totaling 293 GW. Figure 1 shows the LCOE and auction data for onshore wind and solar PV, illustrating the sharp decline in the cost of electricity experienced from 2010 to 2017, and signaling prices for 2020 from auction data. Auctions are particularly useful to estimate cost trends in the near future. In essence, just like computer designers are forward-pricing based on Moore’s Law, wind and solar PV developers are forward-pricing installed costs for up to 3 years.

Figure 1 Global levelized cost of electricity and auction price show downward trends for utility-scale onshore wind and solar PV.[i]

Based on LCOE, the average cost of electricity from onshore wind fell by 23% from 2010 to 2017. Based on auction price, we can expect the average cost of electricity from onshore wind farms to decline a further 17% by 2020, to US4.7¢ per kWh. Overall, from 2010 to 2020, the cost of electricity from onshore wind has seen an average reduction of almost 6% per year, or 55% per decade.

Based on LCOE, the average cost of electricity from utility-scale solar PV fell by 73% from 2010 to 2017. Looking forward with auction prices, we can expect the average cost of electricity from utility-scale solar PV to decline a further 47% by 2019, to US4.7¢ per kWh. From 2010 to 2019, the cost of electricity from utility-scale solar PV has seen an average reduction of 20% per year, or 87% per decade.

By 2019 or 2020, the best onshore wind and solar PV projects will be delivering electricity for less than 2¢ or 3¢ per kWh, as shown by the record-low auction prices for solar PV in Dubai, Mexico, Peru, Chile and Saudi Arabia.[ii]This is not missed by leading industry executives. During the January 2018 investor call, Jim Robo, Chairman and Chief Executive Officer of NextEra Energy, noted:

  • “[Without] incentives, early in the next decade wind is going to be a 2 to 2.5 cent per [kWh] product.”
  • “By early in the next decade, as further cost declines are realized, and module efficiencies continue to improve, we expect that without incentives solar pricing will be 3 to 4 cents per [kWh], below the variable costs required to operate an existing coal or nuclear generating facility of 3.5 to 5 cents per [kWh].”[iii]

This executive is saying that generating energy from wind and solar PV will cost less than just burning fuel in existing plants.

Even in Canada?

In December 2017, the Government of Alberta announced the results of its Renewable Electricity Program, for nearly 600 MW of wind generation to be operational in 2019, at prices ranging from 3.09¢ to 4.33¢ per kWh, setting a new record in Canada.[iv]Those wind farms will be located in Southern Alberta, where the onshore wind resources are the best in Canada.

Already now, and increasingly in coming years, some wind and solar PV power generation projects can undercut fossil fuel-fired electricity generation, without financial incentives, and this is coming to Canada very quickly.

Global averages do not reflect the broad variation in the quality of solar or wind resources at any given location. For example, Figure 11shows the LCOE in 3 U.S. cities for utility-scale solar PV: Phoenix, AZ (a southern high-insolation area), Kansas City, MO (an average city in the U.S.), and New York, NY (typical of the North-East). A utility-scale solar PV plant in a high-insolation area like Phoenix can produce electricity for approximately 30% less than a plant in New York. However, all geographies have seen a decline in the cost of generation. Given the average decline of 20% per year, costs in New York are about 18 months behind costs in Phoenix.

Figure 2 Cost of electricity generated from utility-scale (one-axis tracking) solar PV increases at higher latitudes[v]

Cities with better isolation can be expected to have better solar PV capacity factor, and this is true when comparing U.S. and Canadian cities, as shown in Table 1.

Table 1 Approximate annual generation of a 100-MW tracking solar PV systems in various North American cities[vi]

City Annual generation in MWh for a 100-MW system % vs. Phoenix
Phoenix, AZ 219,000 100%
Kansas City, MO 173,000 79%
New York, NY 153,000 70%
Lethbridge, AB 189,000 86%
Calgary, AB 182,000 83%
Montréal, QC 146,000 67%
Toronto, ON 144,000 66%
Halifax, NS 145,000 66%
Vancouver, BC 135,000 62%

Based on this table, utility-scale tracking solar PV system in Southern Canada generates approximately 62% to 86% of the electricity generated by a similar system in Phoenix, AZ. Southern Alberta has the best solar resources in Canada, above the U.S. average (represented here by Kansas City, MO).[vii]Given that cost of electricity from utility-scale solar PV sees an average reduction of 20% per year, the large Canadian cities are just 1 to 2 years behind Phoenix.

The annual generation stated in Table 1does not reflect diurnal and seasonal variations in output. After all, the sun does not always shine, nor does the wind always blow. A combination of dispatchable generation, transmission networks, demand management programs and energy storage is required to balance the grid, including the variability of wind and solar generation. However, it is interesting to note that the wind and solar resources in Canada are quite complimentary:

  • Geographically, the onshore wind resources are better at higher latitudes, while the solar resources are better in Southern Canada.[viii]
  • In Southern Canada, Alberta and Saskatchewan offer the best onshore wind and solar resources.
  • Offshore wind is available on the Pacific Coast (British Columbia), on the Atlantic Coast (Maritimes provinces and NF&L), on the Great Lakes (Ontario) and Lake Winnipeg (Manitoba).
  • Hydroelectric potential is greatest in Québec and Manitoba.
  • Across Canada, wind resources are, on average, better in the winter, while the solar resources are better in the summer. There is also some hourly complementarity between wind and solar potential.[ix]

References:

[i]       Renewable Power Generation Costs in 2017, International Renewable Energy Agency, 2018, Figure 2.12, p. 50.

[ii]      Renewable Power Generation Costs in 2017, International Renewable Energy Agency, 2018, p. 19-20.

[iii]     http://www.investor.nexteraenergypartners.com/phoenix.zhtml?c=253465&p=earningsRelease, accessed 20180130.

[iv]      https://www.aeso.ca/market/renewable-electricity-program/rep-round-1-results, accessed 20180128.

[v]       U.S. Solar Photovoltaic System Cost Benchmark: Q1 2017, National Renewable energy laboratory, Figure ES-3.

[vi]      http://pvwatts.nrel.gov/index.php, accessed 20180129, and author’s calculations.

[vii]     Calgary is the sunniest of Canada’s largest cities and Edmonton is the third-sunniest. Perhaps surprisingly, Alberta enjoys a much better solar resource than Germany, an early leader in solar PV.

[viii]    See the The Atlas of Canada – Clean Energy Resources and Projects (CERP), http://atlas.gc.ca/cerp-rpep/en/, accessed 20180129, for the wind and solar energy resource potential in Canada.

[ix]      Energy Watch Group, Global Energy System Based on 100% Renewable Energy – Power Sector: Canada, Lappeenranta University of Technology, 2017, p. 5.

Utilities Should Really Show Customers What They Do

The electricity business is highly technical and customers do not understand what their utility is doing for them. This deserves more attention in plain words, and customer communications should not be limited to storms, grid problems and feel-good messages. Plain communication is especially important since the correlations of customer satisfaction with verifiable objective measures of service delivery (such as SAIDI and SAIFI) are very low! There is, however, very strong relationship between the customers’ overall assessment of reliability and their feelings about how the company manages to minimize the number and length of outages and provides accurate estimates of when power will be restored.[i]

Insight:
There is a strong relationship between customer satisfaction and
feelings about what the utility does to reduce outages and provide repair estimates, but
low correlation with actual measures of reliability.

Obviously, this implies that the utility must show what it does to manage outages.

Florida Power & Light (FPL) is a great example of this approach. FPL turns installing smart new devices to its network into local media events – adding an automated recloser to a line becomes newsworthy! The following 3 news clips illustrate FPL’s strategy:

During hurricane Matthew in September 2016, FPL initiated proactive and frequent communications to keep customers and key stakeholders informed, with unity of messages across all channels:[iii]

  • Multiple robocalls to ~3.4 million customers in advance of the storm.
  • Embedded reporters provided with open access to restoration effort.
  • Multiple press conferences (daily) at the FPL command center, in the field and at county EOC’s leveraged new satellite technology.
  • Use of Twitter, geo-targeted paid social media and Facebook Live highlighted challenges in hardest-hit areas reaching millions of customers.
  • Print, radio, TV and billboard advertising prior to, during and after the storm.
  • Daily email updates to employees.
  • Customer service kiosks in hardest hit areas.
  • Thank you letters to stakeholders after the storm.

Not surprisingly, FPL won the ReliabilityOne National Reliability Excellence Award in 2015 and 2016, and the Southeast Region award in 2017 (despite hurricane Irma in September 2017).[iv]

[i]         Assessing Residential Customer Satisfaction for Large Electric Utilities, Lea Kosnik et al., Department of Economics, University of Missouri—St. Louis, May 2014.

[ii]        See https://patch.com/florida/bradenton/fpl-announces-new-storm-hardening-plan-including-major-investments-enhance-electric-system-serving, retrieved 20171230.

[iii]        Grid Hardening & Hurricane Matthew, Ed DeVarona, Senior Director, Emergency Preparedness, Florida Power & Light, https://www.midwestreliability.org/MRODocuments/Hurricane%20Matthew%20Performance%20Presentation%20by%20Ed%20DeVarona%20to%20MRO%20BOD%2003162017.pdf, retrieved 20171230. .

[iv]       See http://www.paconsulting.com/newsroom/releases/we-energies-wins-national-reliabilityone-excellence-award-at-pa-consulting-groups-17th-annual-reliabilityone-awards-ceremony/, retrieved 20171230, for the 2017 awards.

The Sun for a Penny

I recently presented at the Canadian Electricity Association (CEA) on the future of the industry. What would happen to the power industry if the cost to generate solar electricity reached 1¢/kWh? What could be the impact of a carbon tax? What are the business opportunities arising from the need for reliable power? While electric utilities have seen tremendous transitions during the 125-year history of the CEA, the current rate of development is unprecedented. To paraphrase a famous quote by Wayne Gretzky, utilities need to “skate to where the puck is going to be, not where it has been.” This presentation tried to provide power utilities with some insights into the future direction of the puck! See the presentation here: The Sun for a Penny 20170225a

The New Grid Needs to Be a Lot More Complicated

The Old Grid used to be relatively simple, with generation following load:

Old Grid

It is now a lot more complicated:

New Grid

The grid is transforming and getting more complicated.

  • We are decommissioning fossil plants to reduce GHG emission and nuclear plants because of safety concerns.
  • There is only so many rivers, so the solution of building new hydro plants is not sufficient.
  • We are then replacing fossil and nuclear base load plants with renewables that are intermittent.
  • To compound the problem of balancing the grid, loads are also becoming peakier, with reduced load factor. Interestingly, many energy conservation initiatives actually increase power peaks.
  • To connect the new renewable generation, we then need to build more transmission. The transmission network also allows network operators to spread generation and load over more customers – geographic spread helps smooth out generation and load.
  • Building new transmission lines face local opposition and takes a decade. The only other alternatives to balance the grid are storage … and Demand Management.
  • Another issue is that we are far more dependent on the grid that we used to be. With electrical cars, an outage during the night may mean that you can’t go to work in the morning. So, we see more and more attention to resiliency, with faster distribution restoration using networked distribution feeders as well as microgrids for critical loads during sustained outages.
  • Renewable generation and storage can more effectively be distributed to the distribution network, although small scale generation and storage are much more expansive than community generation and storage.
  • With distributed generation, distributed storage and a networked distribution grid, energy flow on the distribution grid becomes two-way. This requires additional investments into the distribution grid and a new attention to electrical protection (remember the screwdriver).

All of this costs money and forces the utilities to adopt new technologies at a pace that has not been seen in a hundred years. The new technology is expensive, and renewable generation, combined with the cost of storage, increases energy costs. There is increasing attention to reduction of operating costs and optimization of assets.

GTM Squared Report

I just finished reading the annual survey of utilities prepared by GTM Squared (http://www.greentechmedia.com/squared/read/annual-survey-report-2016-the-future-of-global-electricity-systems). I found it a useful reference to understand the challenges faced by utilities worldwide, and I thought of sharing some interesting highlights:

  • 3/4 of utilities say that regulatory hurdles are the greatest challenge they face today. Preference is to develop market-based reforms, as well as clear interconnection/net metering rules – in other words, mechanisms that deal with/assign value to Distributed Energy Resources. Note that DER (such as distributed generators and storage) will play an increasing role in utilities worldwide.
  • Half of respondents see the consumers at the forefront of the industry’s evolution. However, it is surprising that utilities in the same survey do not put a greater priority on customer engagement.
  • On storage, respondents see an increasing emphasis toward actual projects, and less on the physics and technology of storage. DER vendors now offer better systems intelligence and grid integration to companies focused on building a next-generation power grid (more sustainable and more resilient). Energy storage is now living up to the hype, having seen record installations in 2015.

Tutorial: Key Players in the Energy Markets

I will be making a conference to investors later this year and I will also be training some people internally at my employer. The topics will touch on the electricity industry structure and I am preparing some material for it.

The industry can be quite complex in some jurisdictions. I boiled the complexity down to just this:

New Picture

Traditional large-scale generator own and maintain coal, natural gas, nuclear, hydro, wind and solar plants connected to transmission lines. Those are large plants – typically hundreds of megawatts.

Transmitters own and maintain transmission lines – the large steel towers seen going from large generators to cities. Those typically run at 120,000 volts and more, up to over 1,000,000 volts in some cases.

Distributors own and maintain the local infrastructure of poles and conduits going to customer sites. Those typically run at 1,200 to 70,000 volts, usually stepped down to 600 volts. 480 volts, 240 volts or 120 volts for connection to customers.

Most customers are connected to distributors, although some large industrial facilities (such as aluminum smelters) are directly connected to transmission lines.

While customers are connected to distributors, they purchase electricity from an independent retailer or from the retail arm of a distributor.

With customer installing distributed generation on their premises, they sell back power to the market, often through aggregators.

Retailers buy electricity from generators in an energy market – like a stock exchange, but for electricity.

By definition, the energy produced at any instant must be equal to the energy taken by customers, accounting for a small percentage of losses in transmission and distribution. (We are starting to see large-scale storage operators, which may act as both consumer and generator, depending they are charging or releasing electricity in the network.) This critical balance is maintained by the system operator that direct generators to produce more ore less to match load; in some case, the system operator will also direct distributors to shed load (customers) if generation or transmission is insufficient to meet the demand.

The next post will deal with energy and money flows in the market.

Covered Conductors Vs. Single-Phase Reclosers

A utility client told me that they were trying out covered conductors on a feeder in a forested area. This was the first time that this large utility tried covered conductors. The objective is to reduce the impact of tree contacts and falling branches that blow fuses and therefore result in permanent outages for customers. In this context, the great length of feeders and the high system voltage (25 kV) make coordinating reclosers and fuses difficult.

Covered conductors have a thin insulation covering – not rated for the full phase voltage, but sufficient to reduce the risks of flashovers and fire when a tree branch falls between phases, when a tree makes momentary contact with a conductor, or when an animal jumps to it. Covered conductors also allow utilities to use tighter spacing between conductors.

While covered conductors help with tree contacts, they also have a number of operational disadvantages:

  • High impedance faults with a downed conductor are more likely, leading to public safety issues, especially since the conductor may not show arcing and may not look as if it is energized.
  • Covered conductors are more susceptible to burndowns caused by fault arcing. Covering prevents the arc from motoring with magnetic forces along the wire, concentrating heat damage. Repair time and cost increase significantly.
  • Covered wires have a larger diameter and are heavier, increasing loading, especially with freezing ice and high wind, which can likeliness of mechanical damages (including broken poles and cross arms), leading again to high repair time and costs.
  • Covered conductors have somewhat lower ampacity at high temperature (worsened by the black color that absorb more heat from the sun), with more limited short-circuit capability. High temperature also degrades the insulation. This results in more design and planning constraints that may increase construction costs.
  • Water can accumulate between insulation and wire at the low point between of a span, causing premature corrosion and weaken the conductor and can lead to failure.
  • Covered conductors must be installed differently than bare ones. For instance, using conducting insulator tie can lead to partial discharges and radio interference.
  • Finally, cost is an obvious issue – replacing conductors on existing lines is extremely expensive, possibly as much as $100k per km.

These issues got me thinking on how I could provide a better alternative. Replacing fuses with single-phase reclosers appears to be an interesting (if unlikely) alternative to covered conductors. Cutout-mounted single-phase reclosers can easily be installed in existing cutouts to protect lateral circuits. Those circuits are then protected against tree contacts without the disadvantage of covered conductors. Coordination with upstream mainline reclosers is eased by making the single-phase recloser faster than the mainline recloser. Cost is clearly lower than re-conductoring.

Full disclosure: I am employed by S&C, and S&C makes a cutout-mounted recloser.

Pseudo-Realtime Voltage Regulation to Increase DG Penetration

Close-loop voltage control in distribution networks traditionally relied on Potential Transformers (PT) on feeders communicating with a control algorithm sending setting signals to voltage regulators and capacitor banks. More recently, Faraday devices have been used instead of PTs, being less expensive to purchase and to install.

What about smart meters with voltage measurement capability? Some smart meters measure voltage at the service point, which accounts for voltage drop in secondary feeders and transformers. There are also far more meters than PTs or Faraday sensors, providing greater coverage. But there is a problem: smart meter networks have long internal latency – it may take minutes for voltage signals to get back to a control center. This renders smart meters unusable in a traditional real-time control loop.

However, analytics could make use of delayed smart meter data, combined it with other data such as weather and historical data, to provide pseudo real-time feedback.

This could prove particularly effective with high level of Distributed Generation (DG) penetration that is affected by weather, such as solar and wind. Where a traditional voltage control system relying on real-time feedback could be overwhelmed or mislead by the variability of renewable generation, a control system relying on deep analytics of smart meter and weather data could be more effective in maintaining distribution grid stability.

Using Analytics to Assess Islanding Risks of Distributed Generators

One of the most critical situations with Distributed Generators (DG – embedded generators in Europe) is that a interrupter on a distribution feeder may trip to isolate a circuit section and the DGs might continue supplying the load on that section, creating an “island”. When load closely match generation in the island, it may be sustained for some time, posing safety hazards – this is known to have caused death.

Distributed generators have various passive or active anti-islanding mechanisms that open a breaker at the point of connection when an islanding condition is detected. However, islanding detection techniques used in small DGs (such as residential photovoltaic generators) are far from perfect – without expensive circuitry, they may not always immediately detect an island when generation and load are closely matched. Therefore, some utilities require that load on any feeder section (i.e., between interrupters) be always greater than generation, ensuring that an island cannot sustain itself. This means that the total distributed generation capacity on a feeder section must be significantly less than the minimum aggregated load on that section. The problem is compounded by the fact the engineers assessing DG connection requests usually do not know actual load and generation per line section – estimations need to be made.

In the end, allowable distributed generation on a line section can be a pretty small number – in Ontario, Hydro One requires that total generation must not exceed 7% of the annual line section peak load – meaning that few customers are allowed to have generators.

Applying analytics on smart meter data can better assess how much distributed generation can safely be connected to a line section. For instance, minimum load may never be correlated with maximum generation – e.g., in hot climates, minimum load occurs at night, when there is no solar generation. Analytics can look into past load and generation records to determine how much generation can be connected without getting into potential islanding condition. Safe generation levels may be many times more than the previous conservative worst-case-that-never-happens engineering guidelines allowed.

Better DG Connection Assessment by Validating Phase Mapping and Tap Settings with Utilities Analytics

Distributed generators (DG – embedded generators in Europe) can cause voltage excursions outside the allowable range and can exacerbate phase imbalance, increasing losses (especially on North American networks). Utilities set engineering rules to try to mitigate those effects, for example by limiting how much generation can be connected per feeder section.

Unfortunately, meter-to-transformer-to-phase (MTP) mapping (MPT in Europe) is notoriously inaccurate, meaning that engineers do not know the distribution of single-phase DGs on a feeder – with DGs often clustered on single-phase laterals, DG dispersal across phases may be far from even. Similarly, distribution transformer tap positions are generally unknown, but often set high because under-voltages was the traditional problem – with DGs, over-voltage can become the issue. This forces engineers to take an overly cautious approach when assessing DG connections or face the risk of network problem later.

In the past, validating MTP mapping and distribution tap settings required extensive fieldwork to track each triplex to a transformer, to track the transformer to a phase, and to visually check tap setting with a bucket truck. Now, analytic applications can correlate voltage levels over time to identify to what transformers and phase each meter belongs, and identify transformers where tap setting is too high or too low. The analytical engine can also correlate service point street address and longitude/latitude coordinates with those of the transformer. The correlations are statistical, but, with enough historical data, the accuracy is equal to or better than a visual survey, at a much-reduced cost.

With reliable phase and tap information, engineers can now assess DG connections requests with greater confidence that voltage stability of the grid will be maintained.