Valuation Models

Because the industry needs neutral offtake valuations.

Why we built this methodology

Shortly after launching our marketplace in April 2023, we checked in with a few of our market participants and made an interesting discovery.​

Why we built this methodology

Developers, who price based on project cost, were often surprised by the bid-offer spread.

Why we built this methodology

And offtakers each had their own model with unique assumptions, meaning it wasn’t always clear to them how others arrived at their prices.​

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Why we built this methodology

No one could point to an unbiased, market-based estimate of value, making it difficult for market participants to agree on pricing.​

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Why we built this methodology

So we started thinking: wouldn’t it be helpful if all market participants could refer to the same price reference?​

Why we built the model

Shortly after launching our marketplace in April 2023, we checked in with a few of our market participants  and made an interesting discovery.

Developers were often surprised by the bid prices posted by offtakers.

And offtakers each had their own model with unique assumption, meaning it wasn’t always clear to them how others arrived at their prices.

No one could point to an unbiased, market-based estimate of value, making it difficult for market participants to agree on pricing.

So we started thinking: wouldn’t it be helpful if all market participants could refer to the same benchmark?

SWRV = 
Shape Weighted RenewaFi Value

We take into account historical LMPs at each ERCOT hub, historical generation data, forward curves from the most reputable brokers, and key contract terms such as start date, duration, and structure.

  • Unbiased and neutral
  • Calculated with industry best practices
  • Developed with market participants and independent consultants

How It's Different

Calculated with industry best practices
Unbiased and neutral
Developed with market participants and independent consultants
Integrates 1400+ marketplace bids and offers

PPA Methodology

The model calculates the value of any PPA in ERCOT. We multiply the expected hourly price of electricity by the expected hourly generation of the relevant facility over the life of the contract.

Expected Hourly Prices

24/7 Value

The 24/7 Value represents where traders agreed to transact today for energy that will be delivered around-the-clock n the future. We calculate the 24/7 Value by averaging several forward block price curves, which we source daily from large brokers.

Scalars

We use scalars to convert the forward block prices, which are expressed monthly, into an hourly price forecast. We derive the scalars by looking at hourly variability in price from the past three years across Houston, North, West, and South Hubs.

Net load

Net load is the amount of electricity demand that cannot be met with renewables and instead requires fossil fuel power plants to generate. When net load is higher, we generally expect prices to be higher, and vice versa. Our current net load assumptions are based on ERCOT and EIA data.

Expected Hourly Generation

Shape Adjustment

The shape describes how much and when a renewable facility is expected to generate. The shape is represented by a 12x24 table, where each cell includes the average amount of energy expected to be produced in each hour (1-24) of each month (1-12) over the course of the PPA.

Shape Risk

Shape risk refers to the potential difference between a facility’s expected and actual generation. To calculate shape risk, we compare how much the given solar or wind shape would have earned over the past three years against what solar and wind facilities actually earned over the same time period.

Economic Curtailment Risk

When electricity supply outstrips demand, the grid sends negative price signals. This is called economic curtailment risk. Parties have three options to address this: they can settle at the PPA price ("No Floor"); they can adjust the PPA price ("Floor: Adjusted Settlement < $0") or they can choose not to settle at all ("Floor: No Settlement < $0"). Our model quantifies all three options.  

BESS Methodology

Our BESS model calculates the value of any storage facility based on its energy arbitrage opportunity. We subtract the value of the bottom two hours of each day from the value of the top two hours of each day.  

Expected Hourly Prices

24/7 Value

The 24/7 Value represents where traders agreed to transact today for energy that will be delivered around-the-clock n the future. We calculate the 24/7 Value by averaging several forward block price curves, which we source daily from large brokers.

Scalars

We use scalars to convert the forward block prices, which are expressed monthly, into an hourly price forecast. We derive the scalars by looking at hourly variability in price from the past three years across Houston, North, West, and South Hubs.

Net load

Net load is the amount of electricity demand that cannot be met with renewables and instead requires fossil fuel power plants to generate. When net load is higher, we generally expect prices to be higher, and vice versa. Our current net load assumptions are based on ERCOT and EIA data.

Expected Hourly Generation

Top Hours & Bottom Hours

TB2 stands for "top-bottom two," or the top two hours and bottom two hours of each day. Following a TB2 strategy, BESS operators purchase energy during the two hours when prices are at their lowest and sell it during the two hours when prices are the highest, thus maximizing the energy arbitrage opportunity.

State of Charge

State of charge refers to the measure of energy stored within a BESS asset at any given time. This metric is crucial because it determines the battery's ability to charge or discharge in response to hourly price signals. A battery can only discharge when prices are high if it already charged earlier that day. Similarly, a battery can only charge when prices are low if it has capacity to fill.

Roundtrip Efficiency

When energy is cycled, some of it is lost in the form of heat or other factors. When calculating the value of a TB2, this loss must be factored in. RenewaFi assumes an 86% roundtrip efficiency, which is the average roundtrip efficiency for BESS bids and offers in the marketplace as of July 2024.

We audited RenewaFi's PPA valuation model and found it to be sophisticated and thoughtful. The resulting PPA price tracker is an elegant tool that distills large amounts of data and rapidly generates an easy-to-understand, functional, and unbiased view of renewable energy pricing.

Neat Clark

VP, Power Strategy, Guidepost Energy

FAQ

What is RenewaFi?

RenewaFi is the marketplace for wholesale renewable energy in ERCOT. Built for originators by originators, RenewaFi helps sophisticated market participants source and evaluate hedges, so they can focus on closing deals. Originators and traders on RenewaFi browse, post, and counter indicative bids and offers – all anonymously. And when they agree on terms, they can match to reveal their identities. RenewaFi increases speed to market, facilitates price discovery, and expedites counterparty matching. Ultimately, the company’s mission is to help renewable energy professionals decarbonize America’s electric grids.

Who is RenewaFi for?

RenewaFi is for originators looking to complete physically-settled offtake agreements in ERCOT. If you are an originator representing a developer, wholesaler, independent power producer (IPP), bank, retail electricity provider (REP), or utility, we welcome you to schedule a demo.

Which markets does RenewaFi cover?

RenewaFi currently covers ERCOT only.

Why are the bids and offers anonymous?

Originators have asked to keep the marketplace anonymous so that they can prospect for offtake agreements without disclosing their identities and signaling their firms' interests. All activity in the marketplace is anonymous until two parties agree to match for a given opportunity, at which time those two parties’ identities are revealed only to one another. This ensures users’ identities remain confidential unless they consent to disclosing them.

What does it mean to “match"?

Market participants “match” when they indicatively agree to a set of key commercial terms. By “matching,” both parties are revealed to one another so that they can continue negotiations and finalize their offtake agreement offline.

How does the chat feature work?

RenewaFi market participants can chat directly and anonymously with each other whenever they are within 10% on price or have exchanged a request to match. The chat feature allows market participants to reach consensus on deal terms quickly and conveniently.

Who leads RenewaFi?

Noam Yaffe founded RenewaFi after working for a leading clean power plant developer, where he contracted nearly 800 MW of offtake agreements in ERCOT. Earlier in his career, he was an investment banker focused on tech M&A.

Who are your investors?

Our investors include founders and early supporters of leading growth companies like Uber, Square, and Oscar Health. They include First Round Capital, Floating Point, Box Group, Powerhouse Ventures, Mantis, Alumni Ventures, and Day One Ventures.

What happens if I match with someone I already know? If we end up closing a deal, would the success fee still apply?

Yes. By going through RenewaFi, you would have been able to test the market for alternatives and better pricing, access comparable deals that influence your pricing strategy, and confirm that the counterparty is genuinely interested in your deal. This represents significant value. Unlike a broker, RenewaFi is a neutral platform where you can engage anonymously with both existing and new counterparties in an innovative and efficient way. In fact, RenewaFi works best when everyone you know is using it. That's how it facilitates increased liquidity and transparency.

How do you calculate the value charts?

Each chart shows the value over time of a specific combination of technology, start date, term length, and delivery point. We calculate each chart by multiplying the expected hourly price of electricity by the expected hourly generation of the relevant technology (solar or wind) over the lifetime of the contract. The result is an objective estimate of the PPA’s value. We then compare that value to the average price of similar offers from our marketplace. The delta between these two figures represents a “green premium” – the extra money a buyer would need to spend above the expected value of the electricity and RECs to enter into a PPA.

How do you estimate the hourly generation of solar and wind assets in the future?

To get the expected hourly generation of the relevant facility, we start with the facility’s shape, which describes how much and when it is expected to generate. Because a facility’s actual hourly generation can vary materially from its expected hourly generation, we consider the risk of over or under delivering to expectations. To quantify that risk, we compare actual, historical generation data from ERCOT to the given P50 generation profile in order to understand shape risk and adjust the PPA value accordingly. Finally, if the PPA does includes a price floor, we also adjust the shape for economic curtailment risk at the delivery point.

How do you convert forwards into an hourly price curve or merchant curve?

Since solar and wind are intermittent resources, their generation fluctuates dramatically, and the value of the generation is highly sensitive to hourly price movements. To analyze these intermittent resources, we transform forward price curves into hourly, rather than monthly, granularity. To convert the monthly block prices to hourly prices, we use hourly scalars. We derive the scalars by looking at the variability in hourly prices from the past three years across Houston, North, West, and South hubs. Specifically, we divide each hourly price by its respective monthly block price (7x8, 5x16, or 2x16) to match the format of the forward block prices. We calculate scalars for each hour of each month. For hour 5 (5:00am) in October, for example, we calculate 31 distinct scalars representing each day in October. Since we look at three years of data, our set of scalars for this hour is three times as large: 93 in total. To estimate the future value of hour 5 in October, we start by randomly selecting a scalar from these 93 possibilities. We follow this process for every hour of every day for the next 20 years. Once we multiply the randomly selected scalar by the relevant block price, we get a new price forecast with hourly granularity.

Given that you’re using historical data to make predictions about the future, how do you ensure that your hourly price curve represents what’s most likely to occur?

We adjust our scalars to reflect how market conditions are expected to change in the future. We do this by looking at net load. Net load is the amount of electricity demand that cannot be met with renewables. It’s calculated as load minus supply from wind and solar. As net load increases, more supply comes from fossil fuels, which tends to be a more expensive means of producing energy. So when net load is high, we expect price to be high as well. The Price Tracker currently uses a base-case scenario for net load based on ERCOT and EIA forecasts. In the future, users will be able to choose from additional net load scenarios or customize their own.

What about unit contingent shapes?

PPAs can be offered in one of two main structures: “unit contingent” or “fixed shape.” Sometimes unit contingent is called “as generated” or “as produced.” In a unit contingent PPA, the buyer agrees to purchase the seller’s energy whenever it is produced. In a fixed shape PPA, the seller promises to deliver a specific, pre-agreed shape regardless of whether or how much the underlying facility actually generates. Valuing unit contingent PPAs presents a challenge because actual generation may differ substantially from the expected generation profile. This is known as shape risk. To calculate shape risk, we compare how much the given solar or wind shape would have earned over the past three years against what solar and wind facilities actually earned over the same time period. This gives us a series of covariance factors for wind and solar. When we multiply these covariance factors by every hour in the 12x24, we convert what is essentially a fixed shape generation profile into a new generation profile with unit contingent granularity.

What is economic curtailment risk and how do you calculate it?

When electricity supply outstrips demand, the grid sends negative price signals to discourage further generation. This is called economic curtailment risk. Parties have three options to address this. First, they can settle at the PPA price ("No Floor") regardless of whether prices are negative. Since this option puts all the risk on the buyer, no premium is added to the PPA price. Second, they can choose not to settle when prices are negative ("Floor: No Settlement < $0"). Since this options puts all the risk on the seller, a substantial premium is added to the PPA price. Third, the parties can adjust the PPA price dollar-for-dollar whenever prices are negative ("Floor: Adjusted Settlement < $0"). Since this option distributes the risk between the two parties, only a moderate premium is added to the PPA price.