Energy security means power that is always available, affordable and socially acceptable. In many Philippine communities, none of the three is guaranteed. Scheduled and unscheduled outages are common, electricity is expensive, and rooftop solar is still out of reach for most households.
A study my colleagues and I at De La Salle University published in the open-access journal IEEE Access asks a practical question: can households and their local government share a solar microgrid in a way that leaves both better off?
The business model
The design is simple to explain.
- Households that want to join buy solar panels and batteries at a discount provided by the local government unit (LGU).
- Homes are connected through a low-voltage DC microgrid.
- Part of the energy each household harvests flows through the microgrid to power public loads, such as streetlights, that the LGU is responsible for. That shared energy pays back the discount.
- Surplus energy can be sold to the main grid.
The catch is that a cheaper deal for households can mean a more expensive one for the LGU, and the reverse. So we built a multi-objective optimization model that minimizes the lifetime cost to the households and to the LGU at the same time, while sizing the panels, batteries and converters. Instead of a single answer, it produces a set of trade-off designs that decision makers can compare.
What the case study showed
We applied the model to a community of 50 households over 20 years.
- Reliability came built in. In every optimized design, solar panels and batteries kept household and community loads powered through simulated blackouts. The hidden cost of outages disappeared.
- Under current conditions, the economics were tight. With today’s prices, no design beat the main grid on lifetime cost for both parties at once. Standalone home solar was more expensive than the grid for both.
- Under the right conditions, everyone wins. When the price paid for exported power rose by 60%, component costs fell by 20%, batteries were replaced twice instead of three times over 20 years, and household capital was capped at PHP 60,000 to 100,000, the model found designs where both households and the LGU paid less than they would on the main grid alone, and less than with standalone solar.
What drives the economics
The sensitivity analysis is where the policy lessons are.
- Batteries dominate. They are the most expensive part of a household system, so battery prices and battery life move the business case more than anything else.
- Buying together helps. Lower component costs, which bulk purchasing across households and the LGU makes possible, cut costs significantly.
- Export prices matter, but less. Proposals for parity pricing under net metering would help, though their effect was smaller than component and battery costs.
- Growth needs a better deal. Under the current design, adding more households raises the LGU’s cost because it gives more discounts. Scaling up requires redesigning the arrangement so growth benefits everyone.
Where the LGU still pays somewhat more than grid power, the extra cost can be justified as an investment in energy security and community resilience. The benefits are also social: participation, awareness and a community that keeps its lights on during outages.
Lessons for leaders
- Make every stakeholder’s objective explicit. Households, local governments, developers and electric cooperatives each have their own costs and incentives. Model them all before anyone signs.
- Run the sensitivity analysis before you commit. Know which prices, costs and participation levels can break the business case.
- Count resilience. Comparing tariffs alone ignores the cost of outages. Put a value on energy that stays on.
- Align policy, procurement and technology. Export pricing, bulk purchasing and longer-life batteries are levers that policymakers, buyers and suppliers control together.
The same approach applies to industrial parks, campuses and commercial buildings: optimize the technical design and the business model together, so the system works for everyone who has to use it and pay for it.