Pexapark's Spanish model lifts a 2027 solar capture factor from 0.45 to 0.82 when a four-hour battery charges only from the plant - grid charging reaches 0.93, Germany's gray case is worth €112, and no contract price is printed
On 3 November 2026 Pexapark said a four-hour battery sized at half the solar plant's power, charging only from that plant, lifts Spain's 2027 capture factor from 0.45 to 0.82. The note calls that an 82% uplift worth €45 a megawatt-hour. The same box, also allowed to charge from the grid, reaches 0.93. In Germany the plant-only case is worth €46 and the grid-charging case €112. The curves are September 2026. The note names no site and no signed price.
A buyer comparing a solar contract with a solar-plus-battery contract is looking at what fills the box. A 3 November note from Pexapark prices two ways of filling it. Neither way is a signed euro rate for one site.
On 3 November 2026 Pexapark published a note on co-located batteries and Spanish solar. A capture factor, as the note defines it, is the solar capture price divided by the all-day baseload price. A factor of 0.45 means the sunny hours earn 45 percent of that all-day price. The note puts Spain's solar capture factor at 0.45 in 2027, and at 0.45 to 0.47 through 2040. It puts Germany's solar-only factor at 0.60 to 0.62. It prints a Spanish baseload curve falling from €131 a megawatt-hour in 2027 to €50 by 2035, and a solar capture price falling from €63 to €25 over the same span. It does not print a multiplication. 0.45 times €131 is €58.95, our arithmetic, which is not the note's €63. This note does not treat those two printed figures as a product.
The battery case. The note adds a four-hour battery at a 50 percent storage power ratio. That means the battery's power is half the solar plant's power. It names no megawatts, so this note invents none. A "green" battery charges only from the plant beside it. The note says that box lifts Spain's 2027 capture factor from 0.45 to 0.82, an 82 percent uplift worth €45 a megawatt-hour. 0.82 minus 0.45 is 0.37, and 0.37 divided by 0.45 is 0.822, our arithmetic, next to the printed 82 percent. A "gray" battery may also charge from the grid. The note says that case reaches 0.93, only 13 percent above the green case. 0.93 minus 0.82 is 0.11, and 0.11 divided by 0.82 is 0.134, our arithmetic, next to the printed 13 percent.
Where the value sits. The note says the green case delivers around three-quarters of the total uplift in Spain, because the lowest prices fall in the middle of the day, when the plant's own output is already there to charge the box. It prints a green uplift of €45 a megawatt-hour in 2027 and a gray uplift of €60. 45 divided by 60 is 0.75, our arithmetic, which is three-quarters. Spring is the sharp line. The note says the April capture factor averages 0.19 across the curve, and green co-location lifts that April figure from 0.19 to 0.80. The green factor peaks at 0.94 in 2029 to 2031, which the note calls roughly double the solar-only level, then eases to 0.84 by 2036. In euro terms the green uplift falls from €45 in 2027 to €17 in 2036, and the gray uplift from €60 to €23. The note's reason is more batteries chasing the same cheap noon and the same expensive evening, while the all-day price itself falls.
Germany is a different pour. The note says a green battery lifts the 2027 capture factor from 0.62 to 0.92, worth €46 a megawatt-hour, and a gray battery reaches 1.29, worth €112. A factor above 1 means the shaped output is worth more than the flat all-day price. The note says the green case captures less than half of the total uplift. 46 divided by 112 is 0.41, our arithmetic. The reason on the page: Germany's midday dip is shallower, and much of the battery's value comes in winter, when the panels are quiet and the evening peak is high. The German gray box depends on grid charging. The Spanish green box, in this model, does not.
A battery is a bucket. It returns energy put into it. It does not make the energy. In the Spanish model, most of the extra value is noon sun moved to a dearer hour. In the German model, a large share of the extra value is grid power poured in when the roof is quiet. A single euro figure that ignores the pour is mixing two jobs. The note also says that from around March 2027, new distribution-connected batteries in Spain take flexible grid access in order to charge from the grid, including fixed charging windows or curtailment by the distribution operator. Grid charging is the dearer permission in that sentence. The note does not print a fee for it.
What the model is, and what it is not. A footnote says the figures are Pexapark forward capture factors from September 2026, for day-ahead revenue only, up to two cycles a day. Annual figures are averages of monthly values. September is the curve date. 3 November is the publication date. There is no site name, no contract term, and no signed price. LevelTen's third-quarter offer index is a different page. That page prints marketplace offers, including €48 a megawatt-hour for Spanish solar-plus-battery offers and €30.93 for Spanish solar on its own. An offer on a marketplace is not this capture factor, and neither page is a factory's signed contract.
Analogy: the battery is a bucket. In Spain, on this model, the cheap water is the plant's own noon, so filling from the panels gets most of the evening value. In Germany, a lot of the valuable water shows up in winter when the panels are quiet, so the same bucket is worth more if the grid may fill it. A price that ignores the pour is mixing two buckets.
Good: A dated note, a plain definition of the capture factor, green and gray cases side by side, Spain and Germany side by side, a September 2026 curve date, a four-hour battery at half the plant's power, day-ahead revenue only, and two cycles a day. The euro uplifts are printed. The shrinkage out to 2036 is printed.
Bad: No site, no signed price, no megawatts, no fee for grid access. 0.822, 0.134, 0.75, 0.41 and €58.95 are our arithmetic. The note prints 82 percent, 13 percent, about three-quarters, less than half, €63 and €131, and it does not print those workings. The curves are September. The March 2027 grid-access line is the note's. A capture factor above 1 is a model result, not a bill.
Ugly: Treating €45, €60, €46 or €112 as a price a buyer has been offered. Treating the Spanish green bucket and the German gray bucket as the same machine. Multiplying 0.45 by €131 and calling the result the note's €63. Pasting LevelTen's €48 onto this page. Reading a 2027 model as power already flowing into a loading bay.
Soft next step: write the green and gray figures on two lines, name Spain and Germany separately, and leave the contract price blank until a signed page prints it.
Source: Pexapark, David Battista, 3 Nov 2026, co-located batteries and Spanish solar value. Primary for the capture-factor definition, Spain at 0.45 in 2027 and 0.45 to 0.47 through 2040, Germany solar-only at 0.60 to 0.62, the Spanish baseload curve from €131 a megawatt-hour in 2027 to €50 by 2035, the solar capture price from €63 to €25, the April factor of 0.19, the four-hour battery at a 50 percent power ratio, the green case from 0.45 to 0.82 and an 82 percent uplift worth €45, the gray case at 0.93 and 13 percent above green, about three-quarters of the uplift from the green case, the gray uplift of €60, April from 0.19 to 0.80, a green peak of 0.94 in 2029 to 2031 easing to 0.84 by 2036, green uplift from €45 to €17 and gray uplift from €60 to €23 by 2036, Germany green from 0.62 to 0.92 worth €46 and gray at 1.29 worth €112, green as less than half of the German uplift, the winter grid-charging reason, and flexible grid access from around March 2027 for new distribution-connected batteries that charge from the grid. The footnote dates the curves to September 2026 and limits them to day-ahead revenue, up to two cycles a day, with annual figures as averages of monthly values. The note prints no site and no signed price. 0.37 divided by 0.45, 0.11 divided by 0.82, 45 divided by 60, 46 divided by 112, and 0.45 times €131, are our arithmetic. The note does not print those workings. LevelTen's third-quarter European offer index, filed on this desk on 28 Oct 2026, is a separate page. Its €48 and €30.93 are offers on that index, not figures on the Pexapark note.