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 Direct Solar Space Heating System Controller
The Direct Solar Space Heating System

This was a highly modified CUSTOM circuit.

This is a Do It Yourself (DIY) IDEA !
This is a project that was done for fun!
No one wants this! There is no market!
Space heating TAKES A LOT OF ENERGY ! It's not
like a well insulated closed off tank of water!
You are basically trying to heat a giant
heat sink (room) that sucks the heat away fast!
Run a normal off grid system with an
inverter and Li-Ion BATTERIES like in this video

WARNING: Voltages of up to 240V DC can be present in this EXAMPLE EDUCATIONAL PROJECT!

  • Save Money - Reduced grid power usage saves you hundreds every year!
  • Maintenance Free - NO compressor, freon or gas to worry about!
  • Less Equipment - Direct, NO batteries, NO inverters, NO charge controllers!
  • Works in Low Temps - Keeps going past Heat Pump cold limits!
  • Starts at 3 panels - Go from 750W to 1500W depending on situation!
  • Uses A Standard Space Heater - SunBeam 1500W 120V quartz space heater
  • Reduce Wood or Propane Use - Less back breaking work and expense!
  • Reduced or No Fumes - Clean Odorless electric SOLAR POWERED heat!
  • Winter Cold Proof - Solar PV panels work better when cold!
  • Freeze Proof - No outside pipes to freeze, solves problems fluid systems have
  • MPPT - Microprocessor controlled constant Maximum Power Point Tracking
  • Starts First Thing - Starts making low heat as soon as the Sun hits the panels!
  • No Batteries - Batteries are a pain! Lots of energy loss, messy, 5 yr lifespan
  • Upgradeable System - Add more solar panels or a second unit as you go
  • Time Of Use Ready - Got high PEAK POWER PRICES? This will help!
  • Eco Friendly - Reduced CO2 emissions! Reduce your carbon footprint!
  • Home Value - You own the solar panels, not the power company!
  • Off Grid - Completely off grid system!
  • Be Prepared - Preppers won't freeze, survivalists be ready!
  • "Smart" Meter Ready - No power company contracts or hassles!
  • UL 1741 Compliant - UL, NEC and NEMA compliant, see Specs below
  • Safety Systems Remain Intact - Heater safety systems are not modified
  • Made in the USA - Designed and manufactured in the USA

  • Some Suggested Uses:
  • Heating Booster - Assists your normal heating system for power bill savings!
  • Directed Personal Heat - Creates a VERY warm "zone" around a workspace
  • Small Cabins - Live in warm comfort!
  • Work Sheds - Small insulated work rooms / sheds can be kept warm
  • Warming Huts - Remote off grid insulated small rooms can be kept warm

Why RENT your power when you can EASILY OWN IT?

These are NOT for sale!
You can contact us if you really want to talk about it.

pic direct space heater system

What this DIY project may do for you:

Heats a small room or space with free solar power.

FREE ENERGY FROM THE SUN can boost your existing heating system.

This is a Do It Yourself DIY kit. Or use a professional electrician to wire the unit. No soldering required

pic electric space heater Using a low cost Sunbeam Quartz Radiant Heater as shown to the right >>> you can heat a small well insulated room or boost your existing heating system.

Heat is energy, if you put this in a room it is going to help heat that room with as much heat as solar panels you can put on it, with very little conversion loss since it's connected almost directly to the solar panels. (you do not connect direct, keep reading)

With the controller's Maximum Power Point Tracking (MPPT), the heating starts the first thing when the Sunlight hits your solar panels. It will match the load (heater elements) to your panels so they are always within their highest power production voltage and amps. You may see 200W of heating first thing in the morning and it goes up from there.

We are NOT saying this will heat an entire home! (unless it's really small) This is not magic. But it is possible to heat a well insulated room fairly well. Having low ceilings helps keep the hot air lower.

BEFORE you build something like this - Prove it to yourself first. Take a small space heater and set it on medium, or over 1000W setting and try that in the space you may want to heat or boost and see how that works out. You will understand approximately the amount of heat you will be getting with this system. Some small 1500W space heaters will drop to 750W or less on "low". The only way to really know is to go buy a low cost Kill-A-Watt or other home AC Wattage reading device and measure the ACTUAL WATTAGE so you can get a real world idea of what we are talking about heat wise here.

GET A DAMN INVERTER INSTEAD! Easier and then you can use the system for other stuff and all year too!

One thing we will say is to sit in front of this heater with only 1000W of panels at about 10AM, you have to put it about 3 feet away or it gets way too hot in that "zone" in front of it!

In an emergency power outage or other situation this could be a winter life saver!

As a workspace "personal" space heater giving you free heat, it really can't be beat!

pic solar panel Things have changed, Solar Panels are now available on a regular basis for less than 80 cents a Watt SHIPPED to your door, making this the low cost choice for solar heating! (solar panels and box not included)

The Direct Solar Space Heating System allows you to use a slightly modified standard domestic Space Heater with standard "24V" Solar Panels starting with a 750W configuration ( 3 x 250W always in SERIES)

Works equally well with "12V" panels. Many different configurations of "12V" panels are possible, check the VOC spec below.

Heater Safety Systems Remain Intact - This is important! All Heater safety features like tip over protection, thermostats and overheat protection remain intact AND ARE NOT MODIFIED!

WARNING! DO NOT TRY TO CONNECT SOLAR PANELS DIRECTLY TO A SPACE HEATER! The design of this controller unit specifically protects the built in thermostats from DC arcing produced by solar panels! DC WILL EAT CONTACTS. Also, any AC fan motor will burn up and be destroyed. You will receive instructions on how to modify this specific model heater to run a DC fan from your same solar panels at the box. It's not difficult and a standard widely available low cost fan can be used. Yes, this radiant heater uses a small fan to move air past the thermostat, not to blow it at you.

Why this infrared quartz heater model? We tested many styles. #1 We want to stay away from forced heat AC fans. #2 The "string" or "coil" type of radiant heaters will "sing" to you a very annoying noise like a de-tuned squealing sick guitar as the MPPT changes and you don't want to hear that. #3 The oil type of heater will work but mostly radiates heat straight up. The quartz heater will make a "hissing" noise sometimes when heating up from being completely cold, it does that normally anyway. Other than that, a very low fan noise.

The Sunbeam infrared quartz heater model is available at Walmart and other places. It is also re-branded (same thing inside) by Holmes, Ecotroinc, and several other companies. If you want to use something else that is your choice but consider the above reasons and it must NOT have any digital electronics or fans that blow heat at you, or other goodies. Just simple passive radiant heat that can run on DC. Just go buy the right thing and be happy. Don't try to use some old junk in the garage or two heaters with lower wattage that will divide the heat, please think. You must know the watts of the heater or if it has a fan inside as they do not say anywhere about a fan!

And yes, the elements glow a nice orange color and the front gets very hot so this is not a choice for people with small children as with any simple space heater.

Solar tax credits and power company rebates may be available! [ Check your State Here ]

pic no inverter or batteries
No battery. No charge controller. No inverter.

Save money on your power bill without messy batteries, expensive charge controllers or inverters. You can pay for all that and still have the hassles of the battery running down, tying into your electrical box circuits, switch over relays, UPSs and more. Batteries can have up to 50% energy loss.

With an inverter you have to balance a your AC loads with your batteries and daily solar panel output wattage, and what about cloudy days? It's not fun adjusting your system all the time to changing conditions. Cheap, inexpensive power becomes a inverter and battery baby sitting job. This cost effective system requires little or no attention.

The Direct Solar Space Heating System has a CPU specially programmed for Maximum Power Point Tracking (MPPT) and continually adjusts during the day to get the most power from the Solar Panels. MPPT is especially needed in the mornings, afternoons or cloudy days to keep the most power pumping into the heating element at all times. If you tried (DON'T) hooking up your solar panels direct, but without MPPT you will get little heat for your investment and have other problems. (See our FAQ page for more on this)

The Direct Solar Space Heating System Unit itself uses little power, has low insertion loss and no bulky wasteful transformer. It's 97% efficient! (pass through)

GET A DAMN INVERTER INSTEAD! Easier and then you can use the system for other stuff and all year too!

Solar panel daily watts = watts off your power bill. Less grid power usage, lower bill.

pic electrical boxes You can buy a more expensive UL Listed electrical box on the Internet or a local Electrical Supply house, your choice. The bigger the box, the bigger the heat sink which may help keep the unit cooler.
Winter efficiency does not decrease like liquid based or Heat Pump systems. No heavy collectors on the roof, just lightweight solar panels.

Fluid based systems also have a grid backup element for dark cloudy days. Many of the standard fluid based systems are equivalent in actual energy put into the use tank as a 750W PV system.

Continues to work even during grid power outages and light cloudy days. No copper piping changes, soldering or expensive pumps to wear out.

THIS IS NOT THE SAME UNIT AS THE HOT WATER CONTROLLER WE SELL! This is a CUSTOM made unit with many modifications

GET A DAMN INVERTER INSTEAD! Easier and then you can use the system for other stuff and all year too!

You are lucky and gifted if you have the experience to do these sort of DIY projects!

Any power reducing modification on a piece of real estate will increase the property value.

One of the biggest energy users in your home, is heating and cooling!

You will now own something of substance and value instead of throwing money year after year into the power company black hole!

Reduce your carbon footprint now! Reduce reliance on foreign oil!

The "future" all electric house is now possible and efficient!

pic American flag The Direct Solar Space Heating System is (mostly) made in the USA! Your purchase helps support local American electronic assemblers, parts suppliers and machinists.

[ Click here to see the Hybrid Controller FAQ page for more details ]

Obey all HEATER WARNINGS and RULES that come with the heater!
Note: If the heater is left in the "ON" position at night, it will come on automatically as soon as the Sun hits your panels!

pic logo The Direct Solar Space Heating System is Patent Pending.

Specs: (preliminary and subject to change)
Absolute Maximum Voltage: 290V DC (panel open circuit should never approach this)
Max Operating Voltage: 240V (operating means when panels are under load)
Max Operating Current: 10A (panels in series always)
Typical Operating V&A: 220V at 8A (only voltage goes up with more panels)
Max Panel Watts: 1500W Solar Panel "sticker" Watts
Solar Panel Wiring Configuration: Always in SERIES (voltage up, amps the same)
Insertion Efficiency: 97% (pass through)
Switch: High tech, latest technology IGBT (mosfet) 80A peak (over designed)
IGBT Gate Drive: 15V, hard off/on for maximum efficiency and quick switching
Microprocessor CPU Controlled MPPT with constant adjustment
UL 1741 compliant when using a UL Listed, NEMA rated enclosure and metal conduit
NEC Article 409 compliant when using a UL Listed, NEMA rated enclosure
Recommended minimum solar panel wattage, unit in box: Around 750W (3 x "24V")
Heating Element: Standard 1500W 120V (no AC fans!)
Load Type: Resistive loads only (no reactive loads like motors or anything with coils)
Wire Size: 16 AWG minimum to the heater, 5 ft max length, shorter is better
#10 AWG from panels in most cases is best (depends on the voltage you are running)
Must be mounted in a larger metal box for a extra heat sink.
This is a transformerless device. No loss through a transformer! No winding short/open.
Controller Size: 4.5"W x 4.5"L x 1.5"H
Always use a thermostat on any element! For indoor use only. Not for use with batteries.
Obey all HEATER WARNINGS and RULES that come with the heater!
Note: If the heater is left in the "ON" position at night, it will come on automatically as soon as the Sun hits your panels!
A professional installer or electrician should be used for any install.
These specifications are subject to change without notice.

This is a low voltage DC off grid system not connected to the electrical grid "mains"

Eaton Disconnect Box: (Home Depot lists them retail for $8, purchased separately)
Note: We only use the disconnect and terminals from this box, get a 10x10x4" box min.
60 Amp Disconnect Model: DPU222RP
UL Listed 74X2 #E132354, #E143893, #E196365
CSA Listed: File 069743 (DH222R)
ANSI certified
NEMA Rating 3R Enclosure
Suitable for CSA Type 3R applications
Meets 2008 NEC Article 422.31 (B) requirements for servicing electric water heaters Copper or Aluminum wire rated (AL or CU Wire)
Canada Alternate Model: 3GAC222NF
Box Depth (in.) 3 in
Box Height (in.) 9 in
Box Width (in.) 5.5 in

As you add more panels you connect them in SERIES. Make sure your OPEN VOLTAGE is well under the ABSOLUTE MAXIMUM VOLTAGE. Operating voltage is always lower than the Abs Max and please don't push the specs, this isn't a car you can "soup up" or CPU you can overclock. Please read the FAQ.

Ground the solar panel frames and use metal conduit for wiring. Recommended additional safety devices you can add are a Lightning Protector, and at higher operating volts over 80V, a DC Ground Fault detector and a DC Series Arc Fault detector (when they become readily available and reliable).

Suggested List Price: NOT FOR SALE This is educational info only!

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Panels Series - Parallel

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Other Enclosures Page

Solar Hybrid FAQ

Solar Hybrid Specs

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BUY IT NOW - Dealer List

Solar Space Heating Sys
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