PLMK merger with Controlled Thermal Resources
Controlled Thermal Resources (United States) — Develops and operates integrated geothermal power and critical minerals extraction facilities, primarily through its flagship Hell’s Kitchen Project at the Salton Sea in Imperial County, California.Pre-revenue: the filings show no meaningful actual revenue for the most recent reported period.
Expected close, as filed: H2 2026.
Announced 8 March 2026.
The symbol the combined company is expected to trade under.
Controlled Thermal Resources Holdings, Inc. (CTR) is a U.S.-based developer of integrated geothermal power and critical minerals projects, headquartered in Imperial County, California, with additional offices in Brisbane, Australia, and Houston, Texas. Founded in 2013 and originally Australian-rooted before redomiciling to the United States in 2022, the company is focused on its flagship Hell's Kitchen Project in California's Imperial Valley, situated within the Salton Sea Geothermal Field. CTR operates through two wholly owned subsidiaries, American Data Power and American Critical Resources, pursuing a vertically integrated engineering model that generates renewable baseload geothermal electricity while simultaneously extracting and refining battery-grade lithium and other critical minerals from the same geothermal brine resource. The project is designed at full scale to deliver up to 650 megawatts of clean power and approximately 100,000 metric tons per year of lithium carbonate, along with additional U.S.-designated critical minerals including potash, zinc, manganese, rubidium, cesium, boron, and strontium. CTR's direct lithium extraction process uses a closed-loop system powered entirely by renewable energy, avoiding the environmental footprint of evaporation ponds or open-pit mining and requiring no offshore processing.
The company is led by CEO Rod Colwell, who also serves on California's Lithium Valley Commission, alongside President Jim Turner, CFO Eric Thayer, Chief of Staff Nicole Colwell, and Chief Communications Officer Lauren Rose, with a board that includes directors David Jackson, Nicholas Cavanagh, and Kemsley Cross, and former Australian Foreign Minister Julie Bishop as a special advisor. The leadership team brings over three decades of experience developing and operating large-scale geothermal energy projects in the Salton Sea region. CTR has raised more than $285 million in private capital to date, with investors including Stellantis, the California Energy Commission, and angel investors, according to PitchBook data. The company has secured a 25-year power purchase agreement with Imperial Irrigation District and has a supply contract with General Motors for battery-grade lithium. Technical and engineering partnerships include Baker Hughes, which completed a comprehensive Field Development Plan and a Definitive Feasibility Study compliant with SEC SK1300 standards, as well as Aquatech for integrated brine processing and Hatch Ltd for engineering. CTR has demonstrated its direct lithium extraction process on live geothermal brine at a 1/15 commercial-scale integrated facility and has invested approximately $185 million in long-lead equipment staged for construction.
In March 2026, CTR announced a definitive business combination agreement with Plum Acquisition Corp. IV (Nasdaq: PLMK), a special purpose acquisition company, at a pro forma enterprise value of approximately $4.7 billion and a pro forma equity value of roughly $5.0 billion. The transaction, unanimously approved by both boards, will result in CTR becoming a publicly traded company on the Nasdaq under the ticker symbol "CTRH," with CTR shareholders rolling over 100% of their equity and expected to own approximately 90.6% of the combined company. The deal includes an earnout provision of up to 100 million shares over ten years tied to share price milestones, a domestication to Delaware, lock-up agreements, and an amended registration rights framework. The merger is expected to close in the second half of 2026, subject to shareholder approvals, SEC registration effectiveness, HSR Act clearance, and other customary conditions. Hall Chadwick served as CTR's exclusive corporate, financial, and lead capital markets advisor, while Cohen & Company Capital Markets advised Plum IV.
CTR is going public via SPAC to accelerate its development timeline and fund the commencement of Stage 1 construction at Hell's Kitchen, which is anticipated to include a 50 MW
Structure & dilution
SEC-primary termsThe headline number ignores the shares that did not pay $10 — the founder promote, PIPE stock and warrants. This is the same deal with all equity claims counted.
Effective equity counts every claim on the post-close company at $10.00 — rollover, public shares, the founder promote and the PIPE. The headline counts only the target.
- PIPE
- ≈ $13M · unsourced
- Min-cash condition
- $100M
- Sponsor promote
- 25%
- Exchange ratio
Company Options, Restricted Shares and Warrants convert at 'the Exchange Ratio (as defined in the Business Combination Agreement)'; the numeric ratio is not disclosed in the 8-K.more ▾less ▴
PIPE contemplated but NOT signed at announcement — Plum IV may enter into PIPE Subscription Agreements from time to time before Closing; no size, price, structure or investors stated.more ▾less ▴
PIPE terms — instrument, coupon, conversion price and any reset floor — are not sourced for this deal. The size above is itself unsourced — a stored figure no filing we hold states — so neither the size nor the terms should be read as cited.
Up to 100,000,000 Earnout Shares to Company Stockholders over a ten-year Earnout Period in VWAP-based tranches; the first tranche of 12,500,000 shares vests at a VWAP of $12.50 or more for 20 of any 30 consecutive trading days.more ▾less ▴
CTRH and Founder Shares Lock-Up Period ” means with respect to each tranche of CTRH and Founder Shares Lock-Up Securities, the period commencing on the Closing Date and ending upon the earliest to occur of (i) the applicable Early Release Date for such tranche pursuant to Section 2.1, (ii) the date that is six (6) months following the Closing Date, or (iii) the Expiration Timemore ▾less ▴
Three different numbers are all called the deal value
They are not the same fact, and only the last one is what a valuation multiple may be struck on.
What Controlled Thermal Resources on its own is valued at, before a dollar of the SPAC's trust or the PIPE reaches it. This is the price agreed for the business itself.
assumes 0% redemptions
Money the transaction puts INTO the company. It is counted inside the equity value above, which is why it comes straight back out to reach the figure below — nobody pays a revenue multiple for a bank balance.
The combined company net of that cash — what the buyers are paying for the BUSINESS. Every multiple below is struck on this figure and on nothing else.
What that price is, per dollar of sales
Enterprise value ÷ EBITDA — not shown
No EBITDA figure for Controlled Thermal Resources appears in any filing we hold, so no EV/EBITDA multiple is shown. We have not inferred one from a margin assumption — a multiple built on an assumed margin measures the assumption, not the company.
What qualifies these figures
- The equity and cash figures above assume NOBODY REDEEMS — the filing's own assumption, and the most favourable one available to it. Public shareholders in this market frequently redeem most of a trust; at a higher rate both figures fall together and the enterprise value the multiples are struck on does not move.
All figures above are stated in EX-99 investor presentation (August 2026 revision)0001213900-26-091866
EX-99 press release, 0001213900-26-024933: proFormaEnterpriseValueM "approximately $4.7 billion" — the sponsor rounding its own figure. A press release is a party's own claim, not a filed table: any stated capitalisation table supersedes it.
Why headline and effective values differ is covered in headline vs effective deal value, in plain English.
The target: Controlled Thermal Resources
from 425The business actually being bought — described from SEC primary filings, with projections labelled as projections.
Develops and operates integrated geothermal power and critical minerals extraction facilities, primarily through its flagship Hell’s Kitchen Project at the Salton Sea in Imperial County, California.
The filings show no meaningful actual revenue for the most recent reported period.
Controlled Thermal Resources — every SPAC that has bid for it, and its listed peers
Expensive or cheap?
vs 2 listed peersA price only means something next to what the same kind of business costs on the stock market. This divides what the buyers are paying by what Controlled Thermal Resources actually sells, and sets the answer against its closest listed comparables — or says plainly when that cannot be done.
SpacBrain’s read on the price
No multiple can be computed
Controlled Thermal Resources has no meaningful revenue yet, so no multiple is computable — this is priced on a story, not on financials. The deal still values it at $3.34bn.
The company reports no meaningful sales yet, so there is nothing to divide the price by.
Pro-forma enterprise value as filed.
No meaningful revenue in the most recent reported period.
Not computable — the filings show no meaningful revenue for the most recent reported period.
$1 of their sales costs $10.89 on the open market. Median of 2 listed companies we judged a true comparable, which individually run from 8.44× to 13.33×. Their share prices are from 15 August 2026, not today.
What qualifies the figures above
- SLI, LAC, FEAM, ATLX, LAR, PLL, ABAT, TMC, CRML, SDST, IPO-GLDO have no revenue to divide by, so they are shown but left out of the peer median.
- UUUU, MOS shown for context only — not close enough to move the median.
The 15 listed companies it is measured against, and why
- SLIno revenue multiple
Standard Lithium is the closest listed analogue - a pre-revenue direct-lithium-extraction developer taking brine to battery-grade product through a first commercial-scale plant with a strategic partner, at the same permit-and-finance stage CTR is at; CTR's own deck names it as a comparable.
- LACno revenue multiple
Lithium Americas is a pre-revenue US lithium developer constructing a single multi-billion-dollar first-of-a-kind project underwritten by an automaker and federal support - the same single-asset, capital-intensive, permit-driven equity story as Hell's Kitchen.
- FEAMno revenue multiple
Operational comp: Specialty Mining & Metals (NEC); micro-cap ($70m); shares lithium, filed, project, extraction, mineral, stage with the target's own description; no forward EV/Sales published — counted as a peer, excluded from the median.
- ORA8.44× revenue
Ormat is the only listed pure-play geothermal power producer and operates plants in the same Imperial Valley resource, making it the direct benchmark for the ~650 MW baseload half of CTR - though it is profitable and in operation, so it brackets the destination rather than the stage.
- ATLXno revenue multiple
Operational comp: Specialty Mining & Metals (NEC); micro-cap ($112m); shares lithium, project, minerals, mineral, critical, located with the target's own description; forward EV/Sales 729.3x.
- SGML13.33× revenue
Sigma Lithium is a deck-named lithium comparable that has crossed from development into production at a similar single-asset scale, giving the clearest read on the re-rating CTR is underwriting.
- LARno revenue multiple
Operational comp: Specialty Mining & Metals (NEC); small-cap ($906m); shares lithium, project, mineral, located, operation, used with the target's own description; forward EV/Sales 3.5x.
- PLLno revenue multiple
Piedmont Lithium is a US-domiciled lithium developer of comparable market size financing itself on offtake agreements and strategic investment rather than operating cash flow, matching CTR's funding model.
- ABATno revenue multiple
Operational comp: Specialty Mining & Metals (NEC); micro-cap ($158m); shares lithium, extraction, from, development, integrated, two with the target's own description; forward EV/Sales 14.6x.
- TMCno revenue multiple
TMC is a pre-revenue polymetallic critical-minerals developer sitting on a very large resource with no production and a valuation driven entirely by permitting and policy tailwinds - the closest analogue for CTR's zinc/manganese/polymetallics stream; CTR's deck uses it as a comp.
- CRMLno revenue multiple
Operational comp: Specialty Mining & Metals (NEC); small-cap ($376m); shares lithium, project, minerals, critical, located, development with the target's own description; no forward EV/Sales published — counted as a peer, excluded from the median.
- UUUU32.06× revenuecontext only — left out of the median
Energy Fuels is a deck-named US critical-minerals and rare-earth processor benefiting from the same domestic-supply-chain policy push, but it already produces and sells material, so it is a policy-thesis comp rather than a stage-matched peer.
- MOS1.05× revenuecontext only — left out of the median
Mosaic is the deck's own potash comparable and prices the ~3.0 Mtpa potash by-product stream, but it is a mature multi-billion-revenue fertiliser producer and shares neither CTR's stage nor its scale.
- SDSTno revenue multiple
Operational comp: Specialty Mining & Metals (NEC); micro-cap ($30m); shares lithium, power, scale, equipment, from, processing with the target's own description; no forward EV/Sales published — counted as a peer, excluded from the median.
- IPO-GLDOno revenue multiple
Operational comp: Non-Gold Precious Metals & Minerals (NEC); shares revenue, not, but, stage, any, development with the target's own description; no forward EV/Sales published — counted as a peer, excluded from the median.
Which companies count as comparable is our judgement, written out above so you can disagree with it. The median is what these shares happened to trade at on the date given — not a price anyone is offering for this deal.
Earnout — the contingent shares
Shares that only vest if targets are hit. They are excluded from the effective value above because they are not equity today — but they are dilution waiting on success.
Up to 100,000,000 Earnout Shares to Company Stockholders over a ten-year Earnout Period in VWAP-based tranches; the first tranche of 12,500,000 shares vests at a VWAP of $12.50 or more for 20 of any 30 consecutive trading days.
Set against the actuals: the target is pre-revenue in its most recent reported period, so every earnout trigger sits above a base of roughly zero.
In plain English
No floor / floorlessthe cash guarantee is gone — the price is unprotected
A SPAC's downside protection is not the cash in trust; it is your right to demand that cash. Once the redemption window closes, the cash stays with the company and the share can trade anywhere.
Dilutionhow much of the company new shares take from you
Sponsor promote, PIPE shares, warrants and rights all issue stock that did not pay $10 for it. The headline deal value is before that; the effective value is after.
Pro-forma equitywhat the company is valued at once the deal closes
The combined company's equity value assuming the announced terms and the redemptions that have actually happened.
De-SPACthe day the SPAC becomes the real company
The shares stop being a claim on a pot of cash and start being equity in an operating business. Roughly 80% of recent de-SPACs traded below $10 within a year.
Outside datethe contractual long-stop for closing the deal
A deadline between the SPAC and its target, not between the SPAC and you. It confers no right to cash, which is exactly why it must never be counted as a redemption window.