Solar’s biggest energy challenge:
Well, not exactly the duck itself… but its shape. Just this last year Vox Magazine released a compelling video about solar’s biggest challenge today called the “duck curve.” The Vox video alone has already passed 1.5 million views, reflecting a growing interest in our country’s energy revolution. This duck curve wastes renewable energy, is very inefficient, and increases your utility bill. Not only do home backup batteries turn out to be the solution to the duck curve, they’re an effective way for homeowners like you to increase their solar savings.
How the Powergrid Works
To understand why the duck curve is a problem, let’s review how the power grid works.
To use a simple analogy, operating the power grid is like operating your car except, instead of drivers, the grid is run by people called grid operators. These grid operators supply the grid with enough power for everyone without overloading it.
However, if they produce too much power, they damage the grid and the excess power is wasted.
Just as with your car, there are more efficient and less efficient ways of running a power plant. You know how your car comes with a highway mpg and a city mpg rating? That’s because your car’s gas mileage is never as good when there’s a lot of stop-and-go, accelerating and slowing down. Likewise, power grid operators try to avoid stop-and-go, ramp downs and ramp-ups which are very inefficient. In other words, grid operators try to optimize power production as the demand for electricity changes throughout the day. Let’s see exactly what that looks like in the next section.
The Duck Curve
This is what a typical day of California’s grid power looks like in 2012. Look at California’s power production with its peaks and valleys spanning the day.
Because these peaks and valleys aren’t drastic, power production can be pretty efficient.
Now let’s look at what happened when solar enters the scene in 2013.
We get a leveling-off in the middle of the day when the solar power generation is at its highest. Why is this? When the sun reaches its peak in the middle of the day, solar systems generate more power.
All that solar energy generated mid-day lessens the amount of power that homeowners need from the utility company.
From 2013 – 2018 watch the duck’s shape emerge from the graph as California continues to adopt solar.
It’s important to notice that the head of the duck (peak demand for grid power at 9 p.m.) immediately follows the body of the duck (valley created by solar). Because of solar’s impact, grid operators have to drastically ramp up power production from its lowest point of the day to meet peak demand at 9 p.m.
That’s not the only problem… When your solar system generates more power than your home actually uses, your surplus power gets rerouted to the grid to be used by the neighbors. Neighbors using your surplus solar instead of utility power further deepen the body of the duck.
Even worse, in order to keep the power plants running economically, utilities at least need to run them at a minimal level (shown by the dotted line), similar to idling your car. This means that they have to keep power production at this level even when demand drops below the line. To prevent the grid from being overloaded, utility companies end up remotely shutting off your solar system, wasting its valuable energy.
How the Duck Curve Affects Homeowners
We’ve seen how the duck curve affects the power grid, but how is it affecting you as a homeowner? The duck curve is affecting you in two ways: increasing your utility’s rate plan and curtailing solar power.
Depending on where you live, utility companies use TOU (Time Of Use) rates or demand charges. These are rate plans that calculate how much you pay for power at any given time of the month. For example,
If your utility charge for using a 100–watt light bulb during any 15–minute period of the month is $0.00083 / kWh (kiloWatt hour), your charge for operating that same light bulb during the 15–minute peak demand period would be $0.74 / kWh. This would be a difference of paying a total of $29.60 / kWh vs. paying only $3.30 / kWh for using the same light bulb.
As you can see, when you use grid power makes a drastic difference in how much you pay. More importantly, the more overall demand there is for grid power at any given time, the higher the charge for using it. Because solar has caused an increased ramp-up to meet peak demand at 9 p.m., it costs the utility company more to generate that power, and consequently costs you more to use it.
Secondly, the duck curve affects you by curtailing solar power. When the power grid is at risk of over-generation, the utility company can remotely turn off your solar system. Not only does your clean solar energy get wasted, but you also can’t get reimbursed for it. Many utility companies use “net metering” or similar programs which essentially credit you for surplus solar power sent to the grid. However, if the utility company shuts off your solar system, they prevent you from earning power bill credits which many homeowners rely on.
As you can see, we’re left with a system that is not only inefficient, it wastes our clean, renewable energy. Most noticeably for you, it increases the cost of grid power.
The problem has become clear: How do we flatten the duck? In other words, how do we take all that surplus solar power generated when the sun is shining, and use it in the evening when we need it most?
Home backup batteries solve the duck curve by storing excess solar power during the day to be used during peak demand hours in the evening.
Installing a home backup battery with each solar system would help level out the duck curve by increasing demand in the afternoon while decreasing demand in the evening. But is this even practical? I mean, you would need a very big battery and very big batteries sound very expensive. What people don’t realize is how much progress battery technology has made in recent years. Home backup batteries are less than a fourth of the price they were in 2010, have a much greater capacity, and are more compact.
The benefits are so substantial that every solar system should be integrated with a backup battery. In fact, I predict that every solar system will be tied to a home backup battery in the near future. We’ve already come to the conclusion that backup batteries would help solve the duck curve and are therefore good for the public, but will you see benefits as a homeowner?
The answer is yes! Integrating your solar system with a backup battery benefits you in three ways:
- With backup batteries, homeowners can access their stored power when disaster hits or the power grid goes down.
- By using stored solar power when demand is high, homeowners can reduce or eliminate their TOU rates and demand charges.
- By leveling the duck curve we can eliminate curtailment and utility ramp-ups, reducing the overall cost of grid-power for each homeowner.
Altaray understands the value of home backup batteries and now offers to install them with your solar system! Specifically, we will integrate your system with the Sonnen EcoLinx. Sonnen is the industry leader in backup batteries and one you can trust to back up your home. It has 20-kilowatt hours of storage with a maximum output of 8-kilowatt hours at any time. Built with Lithium-Ion Iron Phosphate, Sonnen is proven superior in safety, reliability, and performance.
The coolest part of this backup battery is EcoLinx- its smart energy management system. It allows for things like smart weather forecasting for your solar system, smart demand control, and load management for the most efficient use of your solar power day-to-day. Most importantly, you can configure backup power to your most essential electronics for when disaster hits or there’s a power outage… and for an advanced storage system, they’re pretty sleek!
Click here to see if your home qualifies to save money with a solar home backup battery. Our Energy Advisors can help you find out if your home is solar-friendly in minutes.