Business Model
- Business Models for the NFE Microgrid OS
- Solar Plus Battery Economic Case (Sezibwa)
- Battery Arbitrage Economic Case (Sezibwa)
- Optimal Solar and Battery Allocation (Sezibwa)
- Battery Price Break-Even (Sezibwa)
- NFE Commercial Reliable Power Microgrids
- NFE Commercial RPM Finance Glossary
- Solar Sizing Re-run, Sept 2026 (600 Wp panels)
Business Models for the NFE Microgrid OS
[!info] Current working basis — August 2026
Tariff: UEDCL Code 10.2, Q3 2026: Peak 666.5 / Shoulder 562.1 / Off-Peak 429.7 UGX/kWh. The full tariff schedule must remain a configurable model input because ERA/UEDCL rates change periodically. Sezibwa base case: zero export value until site eligibility, interconnection terms, and the applicable export credit are confirmed. All commercial offers should be re-run with site-specific load, tariff, capex, financing, and reliability assumptions before commitment.
Purpose
NFE Microgrid OS needs a business model that creates durable recurring revenue while improving the economics and reliability of community energy systems. Two ownership models remain viable, but the current Sezibwa evidence suggests a clear sequencing principle: scale first through partner-owned deployments, while using NFE-owned projects selectively where the project return and strategic value justify tying up capital.
The operating system is the common product in both models. Ownership determines who funds the assets, carries performance risk, and receives the energy margin.
Current evidence from Sezibwa
The Sezibwa analysis is not a universal tariff card, but it gives NFE a grounded reference case for product and commercial decisions:
| Question | Current finding | Business implication |
|---|---|---|
| What should be added to the existing inverter and 8.9 kWh battery? | Solar first. Adding battery at today's price lowers NPV. | The OS should recommend marginal investments based on the assets already installed, not sell a standard hardware bundle. |
| How much solar? | 4 kWp is the low-spill efficiency sweet spot; 5 kWp is the maximum-NPV optimum. | The recommendation depends on the customer's objective: capital efficiency and minimal curtailment versus maximum total value. |
| What does battery arbitrage contribute? | About 22,000–40,000 UGX/month before fully pricing degradation, depending on backup reserve. | Arbitrage is incremental value from sunk hardware, not the core investment case. Dispatch must exceed marginal degradation cost and preserve the agreed reserve. |
| When does more storage pay? | At the 5 kWp anchor, the first added unit breaks even around 367,000 UGX/kWh, versus about 626,000 UGX/kWh today. | Treat battery price as a procurement trigger. Additional storage may still be justified separately for outage resilience. |
| Can surplus solar be sold? | Not assumed in the Sezibwa base case. | Use zero export value until site-specific arrangements are confirmed; show export as a separate upside scenario. |
Detailed evidence: Solar Plus Battery Economic Case, Battery Arbitrage Economic Case, Optimal Solar and Battery Allocation, and Battery Price Break-Even.
1. NFE-owned energy-service model
NFE finances and owns the supported microgrid assets and sells an energy and reliability service to a landlord, estate, community entity, or other contracted counterparty. The exact structure—PPA, lease, energy-service agreement, or another permitted form—must be confirmed against the applicable licensing, tariff, consumer-protection, and metering requirements.
Assets and responsibilities
NFE funds, owns, and operates the contracted system: submeters, solar, batteries where justified, inverters, communications, and the NFE Microgrid OS control and billing layer. NFE carries financing, asset-performance, collections, maintenance, and technology-obsolescence risk.
Revenue and value capture
- Energy-service revenue: contracted charges for electricity supplied or bills avoided, subject to the approved commercial structure.
- Reliability service: an explicit availability or backup tier rather than an assumed premium hidden inside the energy price.
- Operating efficiency: lower losses, better collections, solar self-consumption, reserve-aware dispatch, and tariff-aware control increase project margin.
- Optional services: installation, maintenance, reporting, or financing fees where separately contracted.
Optimization is not revenue by itself. It improves the margin or service quality of a contracted energy product. The commercial model should therefore distinguish customer charges from internally generated savings.
Investment test
Approve an NFE-owned project only when the site-specific model shows acceptable NPV, IRR, downside resilience, and debt-service capacity after turnkey capex, losses, degradation, maintenance, collections, taxes, and financing. At Sezibwa, the attractive next investment is solar on hardware already owned; that result should not be generalized to a greenfield site where inverter and battery costs are not sunk.
Best fit
- High-confidence load and collections data.
- A creditworthy counterparty or enforceable payment mechanism.
- Strong solar self-consumption and limited dependence on unconfirmed export revenue.
- A strategically important reference site or a return high enough to justify NFE capital.
Key tradeoff
This model captures the most project economics and operational learning, but it is capital-intensive and concentrates construction, credit, regulatory, and long-term asset risk on NFE.
2. Partner-owned managed-platform model
A developer, landlord, estate, community entity, or energy-service partner finances and owns the physical assets. NFE supplies the operating platform, supported controls, deployment services, and ongoing technical operations.
Partner role
The partner funds and owns solar, batteries, submeters, inverters, communications hardware, and other site infrastructure. The partner retains asset-financing risk and receives the energy margin, subject to the commercial agreement.
NFE role
- NFE Microgrid OS licensing and supported device integration.
- Metering, customer accounts, billing, collections data, and settlement reporting.
- Monitoring, alerts, remote operations, and performance reporting.
- Tariff-aware, forecast-aware, reserve-aware, and degradation-aware dispatch.
- Site modelling, investment recommendations, commissioning, and lifecycle support.
NFE revenue
- Deployment fee: site assessment, modelling, integration, commissioning, and training.
- Recurring platform fee: a base site fee plus a usage driver such as connected meters, managed assets, or energy settled.
- Managed-operations fee: optional monitoring, dispatch, incident response, reporting, and maintenance coordination.
- Performance component: only where savings can be baselined and audited; use a share of verified incremental value rather than gross electricity sales.
Hardware support and maintenance
NFE should publish a supported-hardware list and define responsibility by asset. Partner-owned equipment remains the partner's financial responsibility. NFE may provide maintenance directly or coordinate approved providers under a separate service level. Unsupported third-party assets, including generators, are excluded unless explicitly integrated and contracted.
Key tradeoff
This model produces less revenue per site than ownership but requires much less NFE capital, limits balance-sheet exposure, and can scale faster across heterogeneous sites.
Common modelling and operating rules
- Keep tariffs configurable. Store the entire time-of-use schedule, effective dates, fixed charges, taxes, and export credit separately from model logic. Re-run forecasts whenever ERA/UEDCL publishes a revision.
- Model the actual site. Use interval load, outages, collections, existing assets, weather, and installed quotations. Do not transfer Sezibwa results unchanged to another microgrid.
- Separate sunk and new capital. Dispatching an owned battery can create incremental value; buying another battery requires a separate investment case.
- Separate energy and resilience value. Energy NPV should stand on its own. Backup reserve, outage avoidance, and service availability should be quantified and priced explicitly where possible.
- Use a Sezibwa-specific zero-export-value base case. Add export value only as a documented scenario with confirmed eligibility, interconnection limits, and credit terms.
- Price degradation at the margin. Arbitrage should run only when avoided tariff cost exceeds conversion losses, marginal battery wear, and the opportunity cost of reducing backup reserve.
- Treat second-life storage as a hypothesis. Recycled batteries may become attractive, but require a second-life-specific techno-economic model covering acquisition, testing and grading, BMS and pack integration, safety, warranty, heterogeneous health, remaining life, and replacement.
Strategic recommendation
| Situation | Preferred approach |
|---|---|
| Partner has capital and wants operating capability | Partner-owned managed platform |
| Site has strong verified economics, reliable collections, and strategic value | Consider NFE ownership after investment committee review |
| Demonstration or product-learning site | NFE-owned or co-invested, with an explicit learning budget |
| Economics depend on unconfirmed export revenue or speculative battery pricing | Do not finance on the upside case; validate first |
The near-term portfolio should therefore be partner-led and platform-first, with a small number of deliberately selected NFE-owned or co-invested sites. This builds recurring software and operations revenue, expands the data set behind the optimizer, and preserves NFE capital for projects where ownership offers exceptional return or strategic learning.
Decisions and evidence still required
- Define the minimum recurring platform fee and its pricing driver: site, meter, managed asset, or energy settled.
- Define a measurable baseline and audit method before offering performance-based fees.
- Set NFE-owned project hurdle rates, concentration limits, credit requirements, and downside tests.
- Confirm the permitted contracting and electricity-resale structures for each customer segment.
- Publish supported hardware, warranty boundaries, maintenance responsibility, and service levels.
- Build the second-life-specific techno-economic model before presenting recycled batteries as a validated strategy.
- Turn the current optimizer into a repeatable site proposal that reports energy value, resilience value, capex, financing, NPV, IRR, payback, tariff sensitivity, and export sensitivity separately.
Solar Plus Battery Economic Case (Sezibwa)
Data provenance
Underlying data: the aggregate meter meter_100 plus the 10 customer sub-meters, over 2026-03-19 to 2026-08-10, from the modbus energy-logger archive (sources: pi-direct and nextcloud-import), i.e. the pre- and early-OpenEMS period. Load basis is a conservative 21.3 kWh/day.
Note (2026-08-20): the site has since migrated to OpenEMS, which is now the live source. OpenEMS-sourced daily figures from mid-August show inconsistencies (the aggregate roughly doubled exactly at the source switchover, and on some days the customer-meter sum exceeds the aggregate), so they are treated as a data-quality issue to resolve before use; this analysis stays on the validated archive. Phase assignments reflect the wiring as observed up to about May 2026 and should be re-verified against the current OpenEMS setup if any connections have been changed.
Battery Arbitrage Economic Case (Sezibwa)
Data provenance
Underlying data: the aggregate meter meter_100 plus the 10 customer sub-meters, over 2026-03-19 to 2026-08-10, from the modbus energy-logger archive (sources: pi-direct and nextcloud-import), i.e. the pre- and early-OpenEMS period. Load basis is a conservative 21.3 kWh/day.
Note (2026-08-20): the site has since migrated to OpenEMS, which is now the live source. OpenEMS-sourced daily figures from mid-August show inconsistencies (the aggregate roughly doubled exactly at the source switchover, and on some days the customer-meter sum exceeds the aggregate), so they are treated as a data-quality issue to resolve before use; this analysis stays on the validated archive. Phase assignments reflect the wiring as observed up to about May 2026 and should be re-verified against the current OpenEMS setup if any connections have been changed.
Optimal Solar and Battery Allocation (Sezibwa)
Data provenance
Underlying data: the aggregate meter meter_100 plus the 10 customer sub-meters, over 2026-03-19 to 2026-08-10, from the modbus energy-logger archive (sources: pi-direct and nextcloud-import), i.e. the pre- and early-OpenEMS period. Load basis is a conservative 21.3 kWh/day.
Note (2026-08-20): the site has since migrated to OpenEMS, which is now the live source. OpenEMS-sourced daily figures from mid-August show inconsistencies (the aggregate roughly doubled exactly at the source switchover, and on some days the customer-meter sum exceeds the aggregate), so they are treated as a data-quality issue to resolve before use; this analysis stays on the validated archive. Phase assignments reflect the wiring as observed up to about May 2026 and should be re-verified against the current OpenEMS setup if any connections have been changed.
Battery Price Break-Even (Sezibwa)
Data provenance
Underlying data: the aggregate meter meter_100 plus the 10 customer sub-meters, over 2026-03-19 to 2026-08-10, from the modbus energy-logger archive (sources: pi-direct and nextcloud-import), i.e. the pre- and early-OpenEMS period. Load basis is a conservative 21.3 kWh/day.
Note (2026-08-20): the site has since migrated to OpenEMS, which is now the live source. OpenEMS-sourced daily figures from mid-August show inconsistencies (the aggregate roughly doubled exactly at the source switchover, and on some days the customer-meter sum exceeds the aggregate), so they are treated as a data-quality issue to resolve before use; this analysis stays on the validated archive. Phase assignments reflect the wiring as observed up to about May 2026 and should be re-verified against the current OpenEMS setup if any connections have been changed.
NFE Commercial Reliable Power Microgrids
Commercial Reliable Power Microgrids (RPMs)
Phase 2 financial and bankability model | Worship Harvest worked example
|
STATUS |
VERSION |
DATE |
|
Core proposition |
1. Purpose of this document
This pack is intended to support the NFE weekly team review on the emerging Commercial RPM model. It captures the current product logic, a worked Phase 2 case, preliminary financing structure, customer-screening thresholds, model definitions and the decisions still required before NFE treats the model as investment-ready.
-
Reference customer: Worship Harvest Ministries, using customer-supplied UEDCL bills and account movements.
-
Benchmark: Sawa Energy's Bellavista solar + battery lease-to-own proposal was used as a commercial-structuring reference, not as NFE's pricing model.
-
Status: Pre-feasibility / internal investment model. Site metering, EPC quotations, regulatory confirmation and credit underwriting remain required.
2. The Commercial RPM model
|
Phase |
Customer outcome |
NFE activity |
|
1 - Measure & Manage |
Establish an evidence-based load and outage baseline. |
Install interval metering, characterize peak/shoulder/off-peak demand, identify critical loads and quantify current backup costs. |
|
2 - Reliable Power |
At least the contracted critical load remains powered through normal outages. |
Deploy storage, inverter/control infrastructure and enough PV to help finance the reliability layer. |
|
3 - Energy Optimization |
Lower grid dependence and optimize energy cost/reliability. |
Expand PV/storage, optimize dispatch and progressively use the grid as a secondary source. |
|
4 - Ownership Option |
Customer may choose to acquire the installed system. |
Execute a predefined buyout/transfer mechanism that first protects any outstanding lender obligations. |
3. Worship Harvest: current evidence base
|
Metric |
Working value |
How to treat it |
|
Average monthly electricity consumption |
~6.9 MWh/month |
Derived from four supplied detailed UEDCL bills; use as the current baseline, not a guaranteed future load. |
|
Annualized electricity consumption |
~82.9 MWh/year |
Used for the current screening model. |
|
Observed load mix |
~29% peak / 52% shoulder / 19% off-peak |
Useful because the 18:00-24:00 peak period exactly matches the requested six-hour backup window. |
|
Recent utility payment behavior |
Bills in the supplied statement were substantially/fully cleared within the billing cycles shown. |
Positive early credit signal, but not a substitute for full credit underwriting. |
|
Phase 2 reliability target |
At least 6 hours during 18:00-24:00 |
Must be validated with interval data and critical-load definition. |
4. Preliminary Phase 2 technical design
|
Component |
Working design |
Rationale |
|
LFP battery |
120 kWh nominal |
Provides headroom above historical average peak-period energy, plus usable-depth, conversion-loss and reliability reserve allowances. |
|
Hybrid inverter |
50 kW, three-phase |
Provides headroom for instantaneous demand and motor/other transient loads that monthly bills cannot reveal. |
|
Solar PV |
36-40 kWp preferred |
PV is not needed to make a 6-hour evening battery work technically; it is included because avoided daytime/peak grid purchases finance the reliability infrastructure. |
|
Controls / EMS |
NFE Microgrid OS + metering |
Required for dispatch, monitoring, billing, alarms, asset health and later portfolio management. |
|
Important engineering caveat |
5. Commercial model: where the RPM margin comes from
The RPM margin is not a surcharge on the customer tariff. It is the economic spread created when NFE can supply a portion of the customer's electricity at a lower effective cost than the utility tariff while preserving the customer-facing price anchor.
|
Cash-flow layer |
Illustrative annual value |
Meaning |
|
Customer electricity revenue |
~UGX 47.0m |
Energy sold at the utility-equivalent weighted tariff assumption. |
|
Gross avoided utility purchases |
~UGX 34.8m |
Value created by direct PV plus PV shifted through storage to displace grid purchases. |
|
Routine O&M allowance |
~UGX 2.1m |
Annual operating/maintenance budget. |
|
Battery + inverter lifecycle reserve |
~UGX 6.9m |
Explicit reserve contribution for major component replacement rather than assuming these costs disappear. |
|
NFE monitoring/billing/site overhead |
~UGX 1.2m |
Site-level software, monitoring, billing and operating support allowance. |
|
CFADS (internal screening definition) |
~UGX 24.5m |
Cash flow available for debt service after the above conservative operating and reserve provisions, before debt service. |
6. Base-case bankability structure
|
Item |
Working assumption |
|
Installed Phase 2 CAPEX |
~UGX 143m |
|
Customer contract term |
15 years |
|
Senior debt |
50-55% of CAPEX preferred for early projects |
|
Sponsor / investor equity |
45-50% of CAPEX |
|
Target debt tenor |
10 years minimum |
|
Target UGX debt rate |
<=12% if possible; concessional/project finance preferred |
|
Debt Service Reserve Account (DSRA) |
6 months of scheduled debt service |
|
Customer upfront equipment payment |
Zero |
|
Customer tariff |
Utility-equivalent energy tariff, with contractually defined indexation |
|
Ownership |
NFE/SPV during service term; Phase 4 buyout option subject to lender discharge |
7. Illustrative 55% debt case
|
Metric |
Illustrative result |
Interpretation |
|
Senior debt |
~UGX 78.5m |
55% of ~UGX 142.8m CAPEX. |
|
NFE/investor equity |
~UGX 64.3m |
Before DSRA funding. |
|
Annual debt service |
~UGX 13.9m |
Assumes 12% debt over 10 years with level annual debt service. |
|
Base DSCR |
~1.76x |
CFADS / scheduled debt service. Provides material cushion above 1.0x. |
|
6-month DSRA |
~UGX 7.0m |
Liquidity buffer equal to half a year of scheduled debt service. |
|
Unlevered project IRR |
~15.1% |
Return on the project before debt financing, under the current simplified 15-year constant-real-cash-flow assumptions. |
|
Equity IRR |
~15.6-16.0% |
Approximate result depending on how/when DSRA is released. |
|
Financing conclusion |
8. Customer qualification threshold
The current model suggests a theoretical break-even/target-return threshold near 1.5 MWh/month for a customer with a load shape similar to Worship Harvest. For sales screening, NFE should use a more conservative threshold because fixed costs, site complexity, credit quality, solar yield and load shape vary.
|
Monthly usage |
Screening interpretation |
|
< 1.5 MWh |
Usually below current economic threshold for a stand-alone Commercial RPM Phase 2. |
|
1.5-2.0 MWh |
Possible but marginal; requires especially favorable site/load/credit conditions. |
|
>= 2.0 MWh |
Recommended first-pass Commercial RPM qualification threshold. |
|
>= 3.0 MWh |
Strong candidate, subject to solar-compatible demand and site/credit quality. |
|
Worship Harvest: ~6.9 MWh |
Comfortably above the consumption threshold; the remaining work is engineering, regulatory, credit and financing validation. |
9. Bankability risks and mitigations
|
Risk |
Why it matters |
Proposed mitigation |
|
Volume risk |
Customer pays for energy used; NFE debt service does not fall if customer consumption contracts. |
Lower leverage for early sites; strong customer underwriting; termination protection; consider a modest minimum annual energy commitment only where financing requires it. |
|
Tariff/indexation risk |
A fixed customer tariff can become uneconomic as utility prices and operating costs change. |
Contractually mirror the applicable utility tariff structure or define a transparent indexation formula. |
|
Credit/collection risk |
Energy revenue is the project cash flow. |
Credit review, payment history, deposits, remote metering, clear default/curtailment procedures and diversified portfolio. |
|
Technology/lifecycle risk |
Battery/inverter replacement can destroy economics if omitted. |
Explicit replacement reserve, manufacturer warranties, standardized equipment and remote health monitoring. |
|
Performance risk |
PV yield or storage availability may underperform assumptions. |
Conservative yield, performance guarantees where available, commissioning tests and reserve margins. |
|
Regulatory risk |
The legal structure for on-site generation/resale/EaaS must be valid. |
Obtain Uganda-specific regulatory/legal confirmation before financial close and standardize the compliant contract structure. |
|
EPC / construction risk |
Cost overruns or poor installation can impair returns and safety. |
Competitive RFQ, fixed-price scope where feasible, commissioning acceptance tests and appropriate EPC warranties. |
10. Proposed cash-flow waterfall
-
Customer pays NFE for metered electricity under the EaaS contract.
-
NFE/SPV pays utility/grid energy costs and other variable energy costs.
-
NFE/SPV funds routine O&M and operating expenses.
-
NFE/SPV funds the agreed battery/inverter lifecycle reserve.
-
Remaining operating cash is CFADS for lender purposes under the internal screening model.
-
Scheduled senior debt service is paid.
-
Required DSRA top-up, if any, is funded.
-
Residual distributable cash is available to NFE / equity investors.
11. Decisions requested from the NFE team
|
Decision |
Current working position |
Team discussion |
|
Commercial Phase 2 product definition |
Battery reliability + enough PV to support the economics. |
Confirm whether this becomes the standard default or remains site-specific. |
|
Customer tariff promise |
Utility-equivalent tariff, not an equipment lease. |
Define exactly which utility charges are mirrored and how tariff changes flow through. |
|
Reliability promise |
6-hour outage coverage for contracted critical load. |
Decide whether the product SLA should be framed as hours, availability %, or both. |
|
Debt strategy |
50-55% debt for early projects; target <=12%, 10+ years. |
Confirm acceptable leverage and target lender categories. |
|
Customer minimum usage |
No hard minimum in the preferred customer proposition. |
Decide whether a soft minimum annual energy commitment is acceptable when a lender requires it. |
|
Phase 4 ownership |
Predefined buyout from a stated year, subject to lender discharge. |
Agree lockout year and buyout methodology. |
|
Commercial screening threshold |
>=2 MWh/month first-pass screen. |
Confirm and add load-shape, credit and site criteria. |
|
Portfolio/SPV structure |
Preferred long-term financing architecture. |
Decide when to establish the first RPM project/portfolio SPV. |
12. Immediate next steps
-
Install/obtain interval metering for Worship Harvest and identify critical vs. discretionary loads.
-
Request at least two local EPC/vendor quotations for the 120 kWh / 50 kW / 36-40 kWp design range.
-
Refresh the model with quoted CAPEX, warranty terms, installation scope and realistic replacement assumptions.
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Confirm the legally compliant Uganda EaaS / on-site resale structure and required permits/licences/exemptions.
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Complete a customer credit review and obtain a longer utility-payment history if available.
-
Develop the standard Commercial RPM EaaS term sheet: tariff indexation, SLA, deposit, termination, access, insurance and Phase 4 buyout.
-
Prepare a lender-facing model with monthly cash flows, debt amortization, downside cases and covenant tests.
-
Build a pipeline scorecard so NFE can screen commercial leads consistently before spending engineering time.
Appendix A - Model assumptions that must be refreshed before investment approval
|
Assumption |
Current working value |
Validation method |
|
Annual load |
~82.9 MWh |
12 months of bills + interval metering |
|
Solar yield |
~1,500 kWh/kWp/year |
Site-specific PV simulation / irradiation dataset |
|
Installed CAPEX |
~UGX 143m for 120 kWh + 50 kW + 40 kWp |
Competitive EPC/vendor RFQs |
|
Project term |
15 years |
Customer contract negotiation |
|
Debt cost / tenor |
12% / 10 years illustrative |
Lender term sheets |
|
Lifecycle reserve |
Modelled explicitly |
Warranty, cycle-life and replacement-price analysis |
|
Utility-equivalent tariff |
Working weighted energy price from current tariff structure |
Refresh at proposal date and define indexation |
|
Customer load shape |
Historical TOU shares from bills |
Interval metering |
|
Regulatory structure |
Not yet confirmed |
Ugandan legal/regulatory review |
Appendix B - Interpretation discipline
-
All figures are preliminary and intended for internal screening, not a customer quote or investment commitment.
-
Do not present IRR, DSCR or the 2 MWh/month threshold without the underlying assumptions; they are outputs of this model, not universal constants.
-
Equipment prices, tariffs and financing costs are time-sensitive and must be refreshed before every investment decision.
-
The model should eventually move from annual averages to monthly/hourly dispatch so reliability and cash flow are tested together.
NFE Commercial RPM Finance Glossary
Commercial RPM Finance & Energy Glossary
Plain-English reference for NFE commercial microgrid discussions
|
STATUS |
VERSION |
DATE |
|
How to use this glossary |
1. Core product and engineering terms
|
Acronym |
Stands for |
Plain-English meaning |
|
RPM |
Reliable Power Microgrid |
NFE's product model for providing reliable electricity as a service, with NFE owning/operating the enabling infrastructure during the service term and an optional later ownership path. |
|
EaaS |
Energy as a Service |
A commercial model in which the customer buys an energy service (for NFE, metered electricity and reliability) rather than buying the underlying solar, battery and inverter equipment. |
|
C&I |
Commercial and Industrial |
Customer segment covering businesses and institutions such as offices, schools, hotels, clinics, supermarkets, churches and factories. |
|
CAPEX |
Capital Expenditure |
Upfront investment in long-lived assets: batteries, inverters, PV modules, switchgear, cabling, controls, installation and commissioning. |
|
OPEX |
Operating Expenditure |
Recurring costs of running the RPM after construction, such as monitoring, service visits, insurance, communications, billing/admin and some maintenance. |
|
O&M |
Operations and Maintenance |
Activities needed to keep the system safe and performing: monitoring, inspections, cleaning where applicable, repairs, warranty administration and maintenance. |
|
EPC |
Engineering, Procurement and Construction |
The party/scope responsible for final engineering, purchasing equipment, constructing/ installing the system and commissioning it. |
|
BoS |
Balance of System |
All supporting equipment beyond the main PV modules/batteries/inverters: mounting, cabling, protection, switchgear, combiner boxes, earthing and related hardware. |
|
PV |
Photovoltaic |
Solar-electric generation technology that converts sunlight directly to electricity. |
|
BESS |
Battery Energy Storage System |
The complete battery system, including cells/modules and associated controls/safety systems. Often used interchangeably with “battery storage” at project level. |
|
LFP |
Lithium Iron Phosphate |
Lithium-ion battery chemistry commonly used in stationary storage because of its cycle life, thermal characteristics and cost profile. |
|
kW |
kilowatt |
A unit of power: the instantaneous rate at which electricity is being produced or consumed. Inverter size and maximum facility demand are power quantities. |
|
kWh |
kilowatt-hour |
A unit of energy: one kilowatt used for one hour. Customer bills and battery energy capacity are expressed in kWh. |
|
kWp |
kilowatt-peak |
The rated DC output capacity of a PV array under standard test conditions. |
|
DoD |
Depth of Discharge |
The percentage of a battery's nominal capacity that is used before recharging. A 90% DoD on a 120 kWh battery implies up to roughly 108 kWh discharged before other conversion losses/reserves. |
|
RTE |
Round-Trip Efficiency |
The ratio of energy recovered from storage to energy put into it. If 100 kWh charges a battery and 90 kWh is later delivered, RTE is 90%. |
|
EMS |
Energy Management System |
Software/control layer that decides how grid, PV, batteries and other resources operate, and provides monitoring, alarms, data and dispatch logic. For NFE this is part of the Microgrid OS. |
|
TOU |
Time of Use |
A tariff structure in which electricity prices differ by time period, such as peak, shoulder and off-peak. TOU pricing can make stored solar particularly valuable during expensive evening hours. |
|
SLA |
Service Level Agreement |
Contractual definition of the service NFE promises, such as availability, supported critical load, response time or outage-coverage duration. |
|
PPA |
Power Purchase Agreement |
A contract under which one party sells electricity to another under agreed pricing and terms. RPM is broader than a conventional PPA because reliability, storage and operations are central to the service. |
|
SPV |
Special Purpose Vehicle |
A separate legal entity created to own one project or a portfolio of projects. An RPM SPV could hold the equipment, customer contracts, debt and project cash flows separately from NFE's general corporate balance sheet. |
2. Project-finance terms
|
Acronym / term |
Stands for |
Plain-English meaning |
|
CFADS |
Cash Flow Available for Debt Service |
Cash generated by the project that is available to pay principal and interest after defined operating costs. In the current NFE screening model we conservatively calculate CFADS after routine O&M, NFE site overhead and lifecycle reserve contributions, but before debt service. |
|
DSCR |
Debt Service Coverage Ratio |
CFADS divided by scheduled principal + interest for the same period. Example: UGX 24.5m CFADS / UGX 13.9m debt service = about 1.76x. Above 1.0x means modeled cash flow exceeds scheduled debt service; lenders normally require additional cushion. |
|
DSRA |
Debt Service Reserve Account |
Cash reserve maintained to cover debt service if operating cash flow is temporarily insufficient. A 6-month DSRA holds roughly half a year of scheduled debt service. |
|
IRR |
Internal Rate of Return |
The discount rate at which the net present value of an investment's projected cash flows equals zero. In plain English, it is a time-adjusted measure of the return generated by investing capital today and receiving future cash flows. Compare IRR with NFE/investor return requirements and the risks in the assumptions; it is not the same as annual profit margin. |
|
Project IRR |
Project / unlevered Internal Rate of Return |
IRR calculated on the project's operating cash flows before debt financing. It answers: “Does the asset itself generate an adequate return regardless of how we finance it?” |
|
Equity IRR |
Equity Internal Rate of Return |
IRR on the cash invested by NFE/equity investors after accounting for debt drawdown and debt service. Leverage can increase or decrease equity IRR depending on the cost and terms of debt relative to project returns. |
|
NPV |
Net Present Value |
Today's value of future project cash flows after discounting them at a chosen required return. Positive NPV means the modeled project creates value above that required return; negative NPV means it does not. |
|
ROI |
Return on Investment |
A simpler return metric comparing gain to amount invested. Unlike IRR, basic ROI does not inherently account for when cash flows occur. |
|
WACC |
Weighted Average Cost of Capital |
The blended required return/cost of a project's debt and equity capital, weighted by how much of each is used. It is often used as a discount rate or hurdle reference. |
|
LLCR |
Loan Life Coverage Ratio |
Present value of CFADS available during the remaining loan life divided by outstanding debt. It looks beyond a single year's DSCR to the debt coverage over the loan period. |
|
PLCR |
Project Life Coverage Ratio |
Present value of CFADS over the remaining project life divided by outstanding debt. It includes cash flows after the loan matures and is therefore normally higher than LLCR. |
|
LCOE |
Levelized Cost of Energy |
Lifetime cost of producing electricity divided by lifetime electricity produced, discounted over time. Useful for comparing generation technologies, but it does not by itself capture reliability value or the timing value of stored energy. |
|
LCOS |
Levelized Cost of Storage |
Lifetime cost of operating storage divided by the energy delivered from storage, generally accounting for efficiency, degradation and replacement. It is a storage analogue to LCOE. |
|
P50 / P90 |
Probability-based energy cases |
P50 is the energy estimate expected to be exceeded roughly 50% of the time; P90 is a more conservative estimate expected to be exceeded roughly 90% of the time. Lenders often care about conservative production cases. |
3. Non-acronym terms that matter for RPM
|
Term |
Meaning for NFE |
|
Utility-price anchor |
NFE's customer price is tied to the applicable utility tariff or a defined utility-based index, rather than an equipment lease payment. |
|
RPM margin per kWh |
The value NFE creates inside the customer's energy price after accounting for the cost of grid/other energy and RPM operating provisions. It is not automatically an extra charge above the utility tariff. |
|
Lifecycle reserve |
Cash set aside over time to fund major replacements such as batteries and inverters. It prevents the model from looking profitable only because future replacement costs were ignored. |
|
Minimum energy commitment |
A contractual floor on energy purchases that can reduce lender volume risk. NFE may prefer not to use a hard minimum unless financing requires it, to preserve the “pay for what you use” proposition. |
|
Take-or-pay |
A stronger form of volume commitment under which a customer pays for a minimum contracted quantity even if it does not consume it. This can improve bankability but may conflict with the desired RPM customer experience. |
|
Early termination payment |
A payment due if a customer voluntarily exits before the contract ends, typically designed to cover outstanding debt, demobilization and a defined portion of unrecovered investment. |
|
Tariff indexation |
Rules that change the customer tariff over time based on a reference such as the applicable utility tariff, inflation or another agreed index. |
|
Critical load |
The subset of facility demand that must remain powered during an outage. Defining critical load can materially reduce battery/inverter size and project cost. |
|
Bankability |
The combination of predictable cash flows, enforceable contracts, acceptable risks, sufficient coverage, credible counterparties and technical/regulatory certainty that makes a lender willing to finance a project. |
4. The four numbers to remember in an RPM financing discussion
|
Number |
Question it answers |
|
IRR |
Is the project/equity return high enough for the risk and capital being committed? |
|
DSCR |
Does current project cash flow comfortably cover this period's debt payment? |
|
CFADS |
How much cash is actually available to service the debt after operating obligations? |
|
CAPEX per site / per supported kW |
How much capital must NFE deploy to deliver the promised reliability and what size portfolio can available capital support? |
|
Practical rule |
Solar Sizing Re-run, Sept 2026 (600 Wp panels)
This page re-runs the solar sizing from Solar Plus Battery Economic Case (Sezibwa) on three months of live OpenEMS load. It answers one question: is 7 to 8 panels (600 Wp each) still the best PV size for Sezibwa, and does it cut the energy bill in half?
Answer
Yes. With 600 Wp panels:
- 6 panels (3.6 kWp) cut the energy bill by half.
- 7 panels (4.2 kWp) cut it by 55%.
- 8 panels (4.8 kWp) cut it by 58% and give the best 20 year return (highest NPV).
Past about 5 kWp each extra panel adds little. The battery is already full by midday, and without grid export the surplus is wasted.
What changed since August
| Input | August model | This re-run |
|---|---|---|
| Load data | Modbus logger archive, Mar to Aug 2026 | OpenEMS aggregate meter DTSU666 (serial 221123297561), 1 Jul to 28 Sep 2026, 76 days of data |
| Average load | 21.3 kWh/day | 25.8 kWh/day |
| Baseline energy bill | about 374,000 UGX/month | about 454,000 UGX/month |
| Panel size | kWp only | 600 Wp panels |
The model code and economics are otherwise unchanged. One correction was made: the daily average now divides by the hours actually covered by data, not the calendar span, so data gaps (for example the site internet outage of 25 to 26 Sep) no longer understate the load.
Cost of an 8 panel install (at cost)
Priced from the Rincol catalogue (August 2026 buy prices), with the railing at 421,000 UGX per 4 panel kit:
| Item | Qty | Cost (UGX) |
|---|---|---|
| 600 Wp mono panel (GS600N-144M) at 320,250 | 8 | 2,562,000 |
| Railing kit (4 panels per kit) at 421,000 | 2 | 842,000 |
| 6 mm2 UV solar cable at 12,000/m | 40 m | 480,000 |
| PV combiner box (MC4) | 1 | 80,000 |
| DC circuit breaker 20 A | 1 | 25,000 |
| Surge protector (a DC rated one is still to be sourced) | 1 | 35,000 |
| Earthing (rod, clamps, conductor) | 1 | 80,000 |
| MC4 connectors (estimate) | 6 pairs | 48,000 |
| Labour and transport | 1 | 250,000 |
| Total | 4,402,000 |
Panels and railing are 3.4M, and the rest of the balance of system and labour adds about 1.0M. The inverter (3.84M) and battery (5.57M) are already paid for, so these are the only new costs.
Results (600 Wp panels, no grid export, at cost)
| Panels | kWp | Saving per month (UGX) | Bill cut | Solar wasted | Cost (UGX) | Simple payback | IRR | NPV at 15% (UGX) |
|---|---|---|---|---|---|---|---|---|
| 5 | 3.0 | 199,406 | 44% | 4% | 3.44M | 1.4 yr | 69% | 10.9M |
| 6 | 3.6 | 225,904 | 50% | 10% | 3.76M | 1.4 yr | 71% | 12.4M |
| 7 | 4.2 | 247,923 | 55% | 16% | 4.08M | 1.4 yr | 72% | 13.6M |
| 8 | 4.8 | 263,462 | 58% | 22% | 4.40M | 1.4 yr | 71% | 14.3M |
| 9 | 5.4 | 273,637 | 60% | 28% | 5.14M | 1.6 yr | 63% | 14.3M |
| 10 | 6.0 | 281,205 | 62% | 33% | 5.46M | 1.6 yr | 61% | 14.5M |
| 11 | 6.6 | 287,350 | 63% | 38% | 5.78M | 1.7 yr | 59% | 14.6M |
| 12 | 7.2 | 292,746 | 64% | 42% | 6.10M | 1.7 yr | 56% | 14.6M |
Cost is built per panel count: panels, one railing kit per 4 panels, and a fixed 40 m of cable, combiner, breaker, surge protector, earthing, connectors and labour. 4 panels is left out because a 4 panel string (about 175 V) is below the inverter's 200 V MPPT minimum. The SRNE ASP48120SH3 has 2 MPPT inputs of up to 9 kW each at 200 to 650 V, so 5 to 14 panels fit on one string.
For a turnkey quote at Rincol selling prices, add roughly 20 to 25% (the August 7 panel quote was 5.02M at sell prices against 4.16M at cost).
Battery only (the existing SRNE, no panels) saves about 34,000 UGX/month (8%) on the model's arbitrage policy.
How to read it
Recommendation
Install 8 panels of 600 Wp (4.8 kWp) on the existing SRNE inverter and battery, for about 4.4M UGX at cost. That cuts the energy bill by 58% (about 263,000 UGX/month) and pays back in about 1.4 years. 7 panels (4.1M, 55%) is the cheaper option. Going above 8 only makes sense with grid export (net metering) or more battery storage.
Assumptions and caveats
- Weather is modelled, not measured: 5.2 peak sun hours, 0.78 performance ratio, and a seeded day to day variation. Measured site irradiance would firm this up.
- Tariff is UEDCL Code 10.2 Q3 2026 (off peak 429.7, shoulder 562.1, peak 666.5 UGX/kWh). The Q4 schedule takes effect on 1 Oct and should be checked.
- Capex uses August 2026 Rincol catalogue buy prices and the 421,000 railing kit. The catalogue has no DC rated PV surge protector yet (the 35,000 line is the AC one), so budget more for that. Confirm current prices before buying.
- Load covers July to September only, so there is no seasonal variation.
- Battery use: with solar, the battery is charged from solar and discharged through the shoulder and peak periods. It replaces the current grid arbitrage (off peak charge, 21:30 to 23:30 discharge). A 30% reserve is held for backup.
- Per phase limit: the inverter delivers at most 4 kW per phase on battery (see the 27 Sep outage report). Solar does not change that limit.
Reproduce
The model is versioned in the nfe-modbus-energy-logger repository under scripts/solar_sim/ (issue #89, PR #90, in review). From the repo root:
python3 scripts/solar_sim/sweep_bom.py scripts/solar_sim/m100_openems.csv
python3 scripts/solar_sim/nfe_solar_model.py scripts/solar_sim/m100_openems.csv
m100_openems.csv holds the site aggregate energy in 15 minute steps (site totals only, no per customer data).