Frequently Asked Questions

Yes! Our solar factory is humming along at full power and we’re molding tanks every day. See customer photos and comments. Happy customers have picked up 290 gallon, 500 gallon, and our huge 950 gallon tanks from our Kona facility.

We are selling tanks as fast as we can make them and sometimes we sell out.  When that happens, our site will show that the tank may be purchased on backorder.  However, we are making tanks almost daily, so go ahead and place your back-order and that will hold your place in line for the next available tank.  Generally, the wait is approximately 1 week at the most for any back ordered items.  Tank pick-up is BY APPOINTMENT ONLY.  You will have the option to schedule your pick-up date and time after your purchase. If you have any questions, just give us a call at 808-825-4738.


  1. Just place your order for tanks at our Order Page,
  2. Use the big green button on your receipt to schedule a pickup time and date that works for you to pick up your tanks at our Kona location.  Note: Tank pick-up is BY APPOINTMENT ONLY.  Tank pickups must be scheduled to allow us to coordinate the production of tanks and the pickup of YOUR tank.  Thanks for your understanding!

Have questions?  Please contact us.  We’re here to help.

We would love to show you our tanks in person!  However, we are not a traditional store but a manufacturing plant.  Our plant is in a lava field separated from our storage warehouse. For this reason, we ask you to schedule a time to come by to see a tank.  You can do that here.

To provide you with the best value we offer the most popular fitting and lid options on each tank size. We offer a limited number of lid or fitting options (some at additional cost).

No, putting hot liquids into any polyethyelene tank is unsafe! Do not attempt.

Yes, our water tanks are made with materials rated at UV-8.

Tank lifespan varies with installation methods and local conditions. Under normal use, we anticipate 5-7 years. Please see our warranty here: https://bigisland.lm.solar/terms/

Our patented solar molding process eliminates the cost and pollution of burning fossil fuels, allowing us to offer high-quality products at better prices.

Yes, you will be given a specific time to pick up your tank so that someone will be available to assist you in loading your truck.

Yes, LightManufaturing water tanks are made with food-grade, FDA-compliant polyethylene and are suitable for drinking liquids.

Yes. This is something you would do on your own and take responsibility for, but you could cap off the existing bulkhead, drill a new hole 6 or more inches away in a different location and then insert your alternate fittings which you would provide on your own.

The walls of our water tanks vary in thickness. In general, the bottom of the tanks are approximately .35 inches thick and the top of the tanks are approximately .20 inches thick. One of the very unique aspects of our patented solar rotational molding process is that we can control the thickness and we are able to make the bottoms thicker than the top.

Our water tanks are brand new and created here in Hawai’i using solar energy.

We mold food-grade polyethylene, which begins to soften at 240F and melts at 280F. We never burn plastic! The ignition temperature for polyethylene is approximately 439F – we always operate well below this temperature.

We are currently testing methods to recycle post-use plastics, and we hope to bring the technology to Hawai’i soon. 

Our array reflects up to 100,000 Watts of energy onto our molds under ideal conditions. We do not make significant electricity – rather we use solar energy as heat to warm our molds to form plastic parts. We do not store energy or transmit it off-site.

We are proud to be tenants in the Hawaii Ocean Science & Technology Park which is administered by NATURAL ENERGY LABORATORY OF HAWAI’I AUTHORITY. You may find more details and contact information here: http://nelha.hawaii.gov/

Rotational molding, and Solar Rotational Molding (SRM) can use a variety of plastics – including virgin (new) material, and recycled material. Plastics made from fossil fuel sources have many environmental issues, but the longevity and reliability of rotationally-molded plastic parts can make them compelling ‘green’ choices over the life of the product – particularly if some recycled content is used. Note that metal, wood or other materials have their own environmental issues as well.

So while plastics aren’t perfect, they have a lot to offer in the context of big long-lasting objects like water tanks, boats, furniture, and more. We think that single-use ‘ephemeral’ plastics are VERY problematic, and we are exploring ways to up-cycle some of these materials into long-lasting rotomolded products.

[ A great podcast about the issues of single-use plastics is “Waste Land” by Planet Money. Again we’d point out that we think water tanks, kayaks, septic tanks and similar big durable products are quite different in benefit and impact than (for example) disposable plastic toys given away in a fast food kids meal. ]

Solar Rotational Molding is an excellent way to close the loop and reuse post-industrial and post-consumer plastic for new products. Especially important is our ability to recycle materials in the field – near landfills and beaches – without requiring plastic waste to be transported to centralized processing facilities. The cost of transportation makes most plastic recycling uneconomical.

By removing energy costs from the molding process, SRM makes the molding of ANY plastic more sustainable and affordable, while reducing greenhouse gas and particulate emissions. New plant-based plastics may offer a source for more sustainable high performance, rotationally-molded plastics. SRM applies Concentrated Solar Power / CSP to a globally-deployed industrial ”smokestack process”, and converts it into a sustainable manufacturing process – a cleantech ‘good citizen’.

Our water tanks are made by a rotational molding process.  However, unliked traditional rotational molding, our process does not burn fossil fuels to heat and melt the plastic or form the tank.  Instead, we use a reflective process to aim the sun’s heat onto the molds.  As a result, there is no burning of fossil fuels, no smoke, no odors, and no noise.

Solar Rotational Molding

Yes. We make several models of solar powered shredder. These devices allow you to shred mixed plastic types into small particles that can be ingested into LightManufacturing Solar Rotational Molding systems. This allows for closed-loop / local re-processing of waste materials. Shredded plastic is also dense and can be efficiently transported to larger facilities for re-processing.

Yes, Solar Rotational Molding can ingest / use beach-collected plastic waste with good results, particularly if the product design is tolerant of thick walls to make up for the reduced strength of environmentally-degraded plastics. With the use of a small percentage of ‘bonding’ resin (new plastic that is good at binding different plastics and contaminants together) plastic parts can be molded at 60% beach plastic waste or more. Landfill-sourced plastics can also be used, at even higher percentages if of known type (eg sorted polyethylene).

To be clear: single-use ‘ephemeral’ plastics are over-used and have serious environmental issues. On the other hand we see great value in long-lasting, large, durable plastic objects like water tanks, and we are excited by the potential of SRM to ‘up-cycle’ some ephemeral plastics into these products.


SRM™ (Solar Rotational Molding) is a patented process, with rights held by LightManufacturing Inc. who developed the technology. SRM systems are not available in kit form, and they are not public domain. We work with NGOs and non-profits, as well as government entities and commercial partners. Contact Us with your project, we’d like to learn more.

LightManufacturing’s patented SRM (Solar Rotational Molding) process uses sun-tracking mirrors called heliostats, to concentrate solar energy on a rotational mold. We have developed a uniquely capable heliostat, called the H1. Heat from the sun directly warms the mold, melting the plastic. Because the process uses heat directly in the molding process, the system is highly efficient: 75% efficient as compared to typical photovoltaic efficiency of 15% or less. There’s no need to convert light into electricity, nor does energy have to be transported via expensive transmission lines to market.

Zero pollution is generated in SRM, and all fuel costs are eliminated.

Rotational molding is a globally-used technique for making large plastic objects. Over 3.6 billion pounds of plastic are rotationally molded each year. Unfortunately, the process is energy intensive and uses non-renewable energy sources like natural gas and kerosene. Over 18.4 trillion BTU of fossil fuel is consumed by the rotational molding process, generating over 2.15 billion pounds of greenhouse gasses annually.

Rotational molding is an excellent way to make large, life-improving products like water and septic tanks, boats, docks, toys, and much more. Solar Rotational Molding helps this global process cheaper to operate and much more sustainable.

Solar Rotational Molding Systems install into areas as small as 60′ x 60′ (3600 ft2). However, most of this area is unmodified; it can be left as unimproved land, or even planted with low-height crops. Here is how the land is used:

Heliostat array footprint @ 60′ x 10′ (600 ft2)
Target enclosure footprint @ 20 ‘x 8′ (160 ft2)
Raw materials, tools, and finished part storage (typical) 300 ft2

Total: 1060 ft2 So, just 30% of the 3600 ft2 total area is occupied by objects. The balance of the land remains unchanged. Compared with the concrete-slab required to support a traditional rotational molding operation, SRM offers a far less impactful solution. Large SRM systems scale as big as needed – 12 systems pack into a single acre of land.

Most people think of injection molding when they think of plastic manufacturing – this process is very capital intensive, and produces high volumes of relatively small, thin-walled objects – i.e. plastic cutlery, small toys, flashlight bodies, etc.

Rotational molding is best at making relatively large objects – from something 6″ across to very large objects such as 8′ diameter water tanks or 10′ long boats, with walls up to 1″ thick. These large, heavy objects do not pack efficiently, and shipping them is essentially to ‘ship air’. As a result, Rotational Molding is distributed across all markets – European Rotomolders making parts for Europe and for export, Asian rotomolders making parts for Asia and for export, etc. The distributed nature of rotational molding allows LightManufacturing’s SRM process to be deployed as needed in solar-rich regions.

Any rotational molding resin can be molded using SRM, including polyethylene, polypropylene, nylon, and other polymers. The SRM process uses CSP / Concentrated Solar Power to achieve any desired molding temperature, and often with cycle times less than ordinary rotomolding. Contact us to learn how we can help convert your traditional operation to a low-cost, sustainable manufacturing operation.


An apparatus containing a movable or driven mirror, used to reflect sunlight in a fixed direction. As the sun moves across the sky, a heliostat makes small adjustments to the position of a mirror in order to keep reflected light on a target. The larger the mirror mounted on the heliostat, the more energy and light is delivered to the target. Multiple heliostats can reflect light onto the same target to deliver large amounts of heat and light. LightManufacturing manufactures the high performance H1 Heliostat.

LightManufacturing H1 heliostat - lowest cost per watt of any commercial heliostat.   Unique tensioned-membrane mirror is shatterproof, tough, and safer than glass mirrors.  Each H1 heliostat can deliver over 2000 watts of energy to a target, or over 230,000 lumens of light when heliostats are used for day-lighting or similar applications. H1 Heliostat Array, Yucatan  

The standard H1 heliostat ships with a 1.21M x 1.21M (48″ square) aluminum composite reflector.

  • The 48″ square mirror reflects over 1000 watts onto a target in optimal conditions, or over 115,000 lumens if used for lighting applications. This is the most energy/light captured by a commercially available heliostat.

In contrast to the H1, some smaller / consumer-oriented heliostats offer a mirror only .5 square meters in area, reflecting @ 425 watts of energy. It would take 4 or 5 of these small units to equal one H1 heliostat.

The LightManufacturing H1 heliostat is a powerful commercial-grade heliostat, with a number of advantages over ‘home heliostat’ systems.

  • The H1 heliostat uses safe, aluminum composite mirrors which are shatterproof and tough, not glass like other heliostats. The H1 mirrors shrug off impact.
  • The H1 heliostat uses only aircraft-grade aluminum structural elements for maximum durability, not plastic like other heliostats.
  • The H1 heliostat can be aimed exactly using your web browser, unlike other heliostats which require you to hand-aim the mirrors at a target.
  • The H1 heliostat can change target easily between multiple targets you define, unlike other heliostats.
  • The H1 heliostat is MUCH larger and captures more light and heat than small ‘home heliostats’. A H1 with 4′ square mirror has a mirror area of1.5 square meters, as compared to consumer heliostats with mirrors only 0.5 square meters or less.
  • The H1 costs less per watt/lumen than any other heliostat on the market. Purchase price of the H1 may be higher, but when you calculate the cost / square meter of mirror you’ll quickly see the advantage of the H1.
  • You can combine multiple H1 heliostats to deliver unlimited heat/light to targets you define, and you can switch all of your H1s from target to target with a single command.

Yes. Heliostats are a low cost way to capture light and heat and direct it into a building through windows. In many buildings, some rooms never get direct sunlight at all – they face the wrong way. Heliostats placed outside these cold /dark rooms can direct warmth and light into the rooms, transforming them into enjoyable, comfortable spaces. Each H1 Heliostat can deliver over 1000 watts to a room, or over 115,000 lumens of light. Multiple H1s can be combined to warm a single room faster, or you can use several H1 heliostats to warm different spaces simultaneously. Applications include schools, office buildings, homes, industrial workspaces, farm buildings, and many other architectural uses.

The H1 Heliostat is available for sale at our heliostat order page ( click here ). The H1 heliostat is available for sale to the general public in several configurations, and we also offer sales programs for commercial customers with volume purchasing needs

Yes.  In fact, heliostats like the LightManufacturing H1 are one of the simplest ways to add sustainable, low-cost solar heat and light to a new green building project, infill project, or retrofit.  Heliostats are low cost, and supply heat and light through existing building windows. » Read more about heliostats for LEED / green building applications.

No.  The H1 heliostat has an internal microprocessor, and no external computer is needed for regular heliostat operation.  A computer or smart-phone browser IS used for initial setup – eg entering heliostat location (lat/long) time of day, time zone, etc – and for defining the heliostat ‘targets’ – where you want the light and heat from the heliostat to go.   After this initial setup, which is done wirelessly, the heliostat operates totally autonomously.  All it needs is 12V DC power – which can be provided by our optional P1 or P2 solar power supplies if you’re installing the heliostat somewhere without available local power. Autonomous heliostat operation is very important if you’re managing multiple units – you don’t want your entire heliostat array taken offline because of a central computer failure, or because of a wiring problem.  LightManufacturing H1 heliostats are robust and failure-resistant in part because each one operates autonomously.   This is important both for heliostat architectural / green building applications and for heliostat solar thermal manufacturing.

  • lowest price per watt in the industry
  • up to 2.3 M2 mirror area, delivers up to 2050 watts to target per heliostat, or over 230,000 lumens
  • autonomous operation – no computer connection required except for one-time setup.
  • 90%+ efficient reflector
  • NEMA-enclosed microprocessor in each heliostat, providing autonomous operation (configuring / programming one heliostat leaves rest of array operational.
  • Fast switching between user-defined targets – no ‘single-target’ limitation
  • 12V DC power
  • Fast heliostat startup cycle
  • flat-pack form factor for efficient shipping
  • easy field repair / adjustment
  • available wireless configuration and control from your laptop – intuitive & simple
  • scalable:   systems from 1 to 1000+ heliostats.  Unlimited heat / light.
  • robust, rugged design, tolerates 60+ mph wind gusts in any position, 90+ in ‘safe’ position
  • ideal tool for applying Concentrated Solar Power ( CSP ) to industrial processes
  • ideal heliostat for home / office daylighting and heating.
  • reduce or eliminate use of fossil fuels / carbon emissions / carbon taxes
  • generate LEED points or carbon credits for Green Building applications
  • commercial grade construction – all metal, no plastic frame elements.
  • steady wind / normal operation OK to 25 MPH / 11 meters-second
  • gust rating any position OK to 60 MPH / 27 meters-second
  • gust rating ‘safe position’ OK to 95 MPH / 43 meters-second

The H1™ heliostat employs a aluminum composite reflector which is more reflective than the best glass mirrors, but is safe, shatterproof and lower cost. A Vacuum-Focus mirror option (US Patent 9,575,222) allows for 100x concentration of the light for intense heating. The H1 incorporates advanced features including wifi-based wireless remote control and configuration (browser-based, no software required), integral microprocessors, and available on-board solar power systems.

The H1 uses a precise two-axis worm-drive system and stepper motors for accurate positioning.

The LightManufacturing H1 heliostat is an industrial-grade heliostat that combines robust performance with easy setup and operation – and at the lowest price per reflected watt of any heliostat on the market.   Simply put, it costs less to heat a target with the H1 that with any other solution.

Yes. We make several models of solar powered shredder. These devices allow you to shred mixed plastic types into small particles that can be ingested into LightManufacturing Solar Rotational Molding systems. This allows for closed-loop / local re-processing of waste materials. Shredded plastic is also dense and can be efficiently transported to larger facilities for re-processing.

Heliostats are the most efficient and low-cost way to harness solar energy.  The uses for heliostats include:

  • heating homes, offices, and other buildings – one H1 heliostat can deliver over 1000 watts of heat, with no energy bill.
  • providing sunlight to shaded spaces – ‘daylighting’.  Rooms in some buildings always face away from the sun.  One H1 heliostat delivers over 230,000 lumens of beautiful natural light, free.
  • replacing fossil fuel heat in industrial processes – for example, in our solar rotational molding systems, LightManufacturing replaces expensive, polluting gas-fired ovens with an array of silent, clean heliostats.   Ask us how free solar thermal energy can transform your industry.
  • Keeping trees and plants alive and healthy in atria and courtyards or other shaded areas.
  • generating steam / ‘process heat’ for industrial applications
  • enhancing oil extraction
  • reducing the moisture content of crops – eg drying nuts prior to roasting, drying seafood
  • industrial-scale cooking
  • sterilization of medical equipment
  • melting snow and ice
  • electricity generation in ‘power-tower’ applications
    …and much more.