Puerto Rico Solar and Batteries
Maria, a category five hurricane, smashed into the island of Puerto Rico in September of 2017. The result was a blackout lasting weeks for the entire territory and months for many individuals. There is no simple reference to the details of the situation and potential solutions. Our team at WattWatt will continue to author these blogs as we learn more to help understand how energy plays a role in the future of Puerto Rico.
Puerto Rico’s electrical grid had major issues before the 2017 hurricanes passed through. While Hurricane Maria certainly caused widespread damage to the infrastructure, the current state of the grid would still be a disaster without the additional damage. Here’s what we’ve learned so far are the causes:
- The Commonwealth’s government run utility, PREPA, was $9 billion in debt before the hurricane. This is due mostly in part due to a mixture of very high cost of generation, misallocation of funds, and non-payment on utility bills. Rebuilding and reinforcing just the transmission lines will cost $4.9 billion through 2027 (this doesn’t include damage from future storms).
- The generation and transmission on the island is centralized, with generation in central locations and consumption spread out. This causes a high dependency on long transmission lines running across difficult terrain. Burying high voltage transmission underground can cost 5 to 10 times more per kilometer than overhead. This is due to the need for thicker wires which create less heat, an issue when lines are buried underground.
- Misaligned interests of the personnel running and working for PREPA. There does not seem to be a strong interest in reducing the debt load of the utility through lower generation costs and more reliable structure.
- The utility has seen a significant loss in skilled employees over the last few years. A primary reason for this was cost reduction- PREPA forced many of its employees to take their pensions early to reduce payroll. Meanwhile, there remains a strong entrenched union among the remaining employees.
- A lot of people have left Puerto Rico, around a quarter million, primarily for the US states. This means less utility customers and less need for existing generation but also less paying customers for the utility company.
- Puerto Ricans consume around 2/5 of the electricity per person of people in the 50 States. Meanwhile, the rate of electricity is almost the highest among any US State (and on the way to being the highest).
The current situation of the electrical grid and generation can be described as crumbling, gummed up and shrinking. 85% of the transmission was wiped out during hurricane Maria. The average age of the generator facilities is about 40 years old (this is very high) and mostly relies on #6 and #2 fuel oil (this is among the most expensive sources of energy and pollutes substantially more than other sources).
The 2,416 km transmission system forms a ring around the island, with several 230 and 115 kV lines crossing the mountains from the south (generation) to the north (demand). They are exposed to high speed winds up the mountains and only 15% of the lines were built to handle even category 4 hurricanes.
Hurricane Maria is considered to be among the strongest hurricanes to hit the United States in recorded history. Only two weeks earlier, Irma also passed through Puerto Rico. Sufficient to say, tall, thin transmission lines sticking up in the mountains could not fare well in these conditions. Maria moved through the major transmission crossing from the south to the north, cutting off not only the southeast corner but also San Juan, the capital.
People in mountain towns have not only been without power since Hurricane Irma (which passed through before Hurricane Maria), they have been taken off the figures used by PREPA for showing percentage of customers reconnected to power since Maria. People in these situations cannot store perishable food in their turned off refrigerators, use the oven or television, or even turn on lightbulbs in their houses at night.
The Synapse Report on the condition of PREPA was not kind to the accounting of the utility company or its competence in ensuring the transmission system is maintained and generation is kept efficient.
The overwhelming issues facing Puerto Rican electrical resilience are:
- Risk of losing transmission in a storm, causing blackouts
- Very high costs of generation from oil
- Central utility with misaligned incentives, leading to skyrocketing debt and inefficient management of new generation and payment collection
- Looming debt owed by the utility, which will add cost to the utility generated electricity for decades
‘It’s a bad situation! We get it. What is your point?’
We’d like to propose a solution, what believe to be the only solution, to this overwhelming problem: distributed generation, energy storage and microgrids. The overwhelming issues with the Puerto Rico can be solved with these systems, including solar PV generation, battery backup systems, and local distribution controlled by software specific for this application.
Stage 1:
Backing up essential infrastructure with on-site generation and battery backup, such as:
- Hospitals
- Emergency shelters
- Police and fire fighter stations
- Drinking water facilities
- Shipping ports
Stage 2:
Houses tying into each other in neighborhood systems. Houses can install their own rooftop generation and pool between them to install a neighborhood battery backup system.
Here’s the math:
- One 2,200 sq ft house with AC: 36 kWh per day
- Annual electrical cost ($0.28 per kWh): $3,630 per year
- One solar PV system (9kW, $3 per Watt DC): $28,000 per 30 years
- Enough battery backup (Quote from Tesla’s site): $14,000 per 10 years
- We will write an additional article at a later time to explain how important cost of capital (borrowing) is to pricing your solar system and the electricity generated by it.
Important caveats include:
- Tesla is one of the more expensive options but comes with high end technology, backed by a more established company, and just look great.
- While the utility charges around $0.28 per kWh now, that rate is almost guaranteed to continue to climb as the utility will need to pay its debts, upgrade both transmission, distribution, substations, and most of its generation that is all aging
Stage 3:
Department of Economic Development and Commerce Secretary Manuel Laboy told Bloomberg that they are considering “a series of micro-grids and regional grids that use solar and battery technology, along with other renewable sources.”
Municipalities, towns and cities can organize the construction of their own microgrids and finance it using municipal bonds. This is certainly in the public interest and something relevant to their duties as a government.
What Puerto Rico can do to allow this to succeed:
- Quality RFP (request for proposal) system that allows installation and development firms to bid for projects based on merit
- Clear guidance on how the bankruptcy of PR’s utility company, PREPA, will be handled
- Some form of assurance that regulation of installations will be efficient and without delays
- Combat the United States House Committee on Natural Resources’s Republican led goal of mandating that natural gas generation take a central role in the future of the grid of Puerto Rico. Natural gas will require long distance transmission, importing fuel leaving the island reliant on others, and cost more in the long term. This is without accounting for the pollution, of course. The Republicans questioning why renewables are being pursued have shown a lack of knowledge on the topic and unwillingness to be educated, as well as being funded by fossil fuel firms.
- Stop handing out free electricity. A 2014 consultant study found that municipalities had benefited from at least $420 million worth of free electricity. 288 government bodies were delinquent in their payments up to around $300 million. This removes the incentive for energy efficient behavior and costs the utility large sums of their revenue.
Existing Examples of Success
- Ilumina: 20 MW PV in the south, in the municipality of Guayama
- San Fermin: 26 MW PV, near Loiza in the northeast
- Puerto Rico Convention Center: 5 MW PV rooftop system
- Culebra Wastewater Plant: 30 kW + Tesla batteries on the island of Culebra. Built since the underwater cables from the main island were put out of commission by the hurricanes for the next 4 years
- US Army Corp of Engineers microgrids: Culebra Island, Patillas, Maunabo, Naguabo, Yabucao, and at least 4 others. These are oil generator based microgrids but they prove the ability of a microgrid to be reliable on its own.
- Tesla microgrids: at least 6 installed on the islands of Vieques and Culebra. Soon after Maria hit, Tesla installed a solar + battery system for a childrens hospital near San Juan, in addition to 662 other locations backed up by Tesla batteries. Tesla claims to be working on about 11,000 more battery projects on the island.
- Sonnen microgrids: donated at least 10 microgrids so far.
- Resilient Power Puerto Rico microgrids: raised at least $625,000 and have built at least 15 solar + battery microgrids, with a stated goal of 100 in total.
- Blue Planet Energy: installed at least 3 microgrids in PR so far.
- Existing portal for microgrids: http://energia.pr.gov/numero_orden/cepr-mi-2018-0001/
Based on the evidence of the costs and risks of maintaining a centralized, transmission and fossil fuel based electric grid, we believe the distributed generation microgrid solution is the only rational way forward for Puerto Rico. As storms become more intense this century, the costs of fossil fuels like coal, oil and gas increase, and Puerto Rico seeks self sufficiency, we think microgrids will shield the commonwealth from incoming problems.
“The appeal of microgrids is of course that they’re much more durable in the face of some kind of a storm,” said Ashley Dawson, author of the book Extreme Cities: The Peril and Promise of Urban Life in the Age of Climate Change. “In terms of Puerto Rico’s vulnerability to hurricanes and other natural disasters, it’s a no-brainer.”
