Our solar panel mount is designed for renters! It installs easily in most double-hung windows - in a similar way as a window-mounted AC. The temporary installation is minimally-invasive so you don't need to deal with losing your security deposit. It supports up to 60 watts.

Our mount comes in two sizes, for window openings 22"-29" and 29"-36.5". Use our sizing tool to determine which size is right for your window. Additional sizing info and installation instruction can be found in the installation instructions.

This product works with most double-hung windows, similar to the one pictured in the product photograph! Windows of this type have vertical channels on the sides. Your window must have a free channel roughly 3/4" wide on both sides to install this product. This is the only type of window this mount is intended to be used for in a non-invasive reversible way i.e. you can easily remove it without permanently impacting the structure. It will not work with other types of windows (single-hung, encasement, etc.).

The cables enter through the bottom of the window, via our included insulated cable entry strips.

We recommend pairing the mount with a solar panel prewired with MC4 cable connectors and using a UL certified all-in-one LiFePO4 power station from a reputable manufacturer. An in-line MC4 fuse and MC4 extension cables are also recommended. We've compiled a list of 3rd party components to help you. We cannot guarantee any product listed will work with our mounting system in your specific situation. Consult our system sizing tool and our product manual for information on sizing a system and choosing components.

Product Versions

All window mount product variants are currently available for beta testing. You can purchase the mount alone or bundled with a 50W solar panel.

• V1b-small (mount only, for window openings 22"-29") - $225
• V1b-large (mount only, for window openings 29"-36.5"_ $225
• V1b-small with 50W solar panel (for window openings 22"-29") - $275
• V1b-large with 50W solar panel (for window openings 29"-36.5"_ $275

Patent pending.

FAQ

What size solar panel can I use?
This device is intended to be used with a standard rigid solar panel, up to 60W. The solar panel width should never exceed the width of the window opening. Flexible solar panels should only be used in short-term low-wind situations.

How do I know if it will fit in my window?
The product is designed to be used in double-hung windows. It will work with most metal-framed double-hung windows and some wood-framed double-hung windows.

A double-hung window is the kind with 2 parts - a top piece that slides down and a bottom piece that slides up. These pieces are called sashes. The window frame usually has channels on the sides for the sashes to slide in. Our mounting system uses on these channels to make the installation easy and safe.

Follow our instructions to measure your window before ordering.

Note that the channel our system uses is often used by the bug screen and it may not work with both simultaneously.

We are developing adapters for our mounting system to work with a wider range of wood-framed double-hung windows and some types of single-hung windows. You can inquire about user-testing these adapters by emailing yo@energytransitiondesign.com

How much light will it block?
It depends on the size of your solar panel. A 50W solar panel is around 22" square inches. The mount is designed so the solar panel hangs down, below the window frame, a little bit. This helps limit how much of your window is blocked by the solar panel. Solar panels are basically all rectangular, but you can choose panels that are more elongated or more square depending on what you think will be best for your window.

Can you help me select a solar panel and power station that works with this mount?

Yes! We now offer the option of ordering the window mount with a solar panel!

Email yo@energytransitiondesign.com for additional support.

In addition to our solar panel mount, a typical system includes a solar panel and power station. We have compiled a list of these products from 3rd party manufacturers in this spreadsheet. Note that all of these solar panels will not necessarily work with all windows and you will need to decide for yourself what size battery is appropriate for your use case. Follow our instructions to determine which solar panel will work with your window before ordering. Additional information that can help you make your decision can be found in the window mount manual.

What can it power?
It depends on the size of your solar panel, how much sun it is exposed to, the size of your battery, and your energy consumption habits. For example, you may choose to slowly fill up a large battery and use a lot of energy every few days or use a smaller battery and use a little energy every day.

Average Daily PV Yield (WhDC) with a south facing 50W Solar Panel, by City

City	March	June	September	December
NYC	235 Wh	257 Wh	258 Wh	161 Wh
Chicago	218 Wh	275 Wh	261 Wh	133 Wh
LA	300 Wh	308 Wh	341 Wh	241 Wh
New Orleans	274 Wh	249 Wh	284 Wh	220 Wh

Estimated daily run times with 85% efficient inverter, NYC in June

Device	Power	Run-time
Smart Phone	5 W	43.69 hours
LED bulb	6 W	36.4 hours
WiFi router	12 W	18 hours
Fan	50 W	4.37 hours
Laptop	50 W	4.37 hours
Nebulizer	60 W	3.6 hours
Refrigerator	100 W	2.18 hours
PA System	300 W	0.73 hours
Air Conditioner	600 W	0.36 hours

Find out how many sun-hours your location gets with NREL's PV Watts calculator.

How much will a full system cost?
About $400-$600. Our mount costs $225. The cost of the rest of the components depends on how you plan to use it. A 50 watt solar panel usually costs between $40-$80. Most users will want to connect the solar panel to a LiFePO4 (LFP) power-station battery, which starts as low as $150. In states that have legalized plug-in solar, you can connect your solar panel directly to the grid via a microinverter, instead of using a battery. Microinverters usually cost $250-$350.

Will I save money by using it?
It depends on the cost of your electricity and your energy consumption habits. In most cases, a system of this size does not allow you to save money directly, but it may be valuable to you in other ways - like providing power in a black out or giving you more control over the energy you consume.

Why is this system more expensive than other types of mounting systems?
This is the only systems designed to be installed on the outside of a window in an accessible and reversible way. It is designed to be minimally invasive, for renters in multifamily buildings who can't make permanent changes to the structure and will want to take their solar panel with them if they move. Safely and easily securing a solar panel to a window is more complex than simply plopping it on the ground or even attaching it to a balcony, which is why those systems tend to be cheaper. As we scale up production in the future, we will hopefully be able to bring the cost down as our little company grows.

How long does it take to assemble and install?
If its your first time installing the system, it usually takes around 1 hour to assemble. Once assembled, the installation process is similar to installing a window-mounted AC.

Do I need to screw it in?
The mount can hold itself in place without screws, but in most cases you should screw it in. The device is screwed in through the legs, into the sides of the window frame. You should absolutely screw it in place if:

• the installation location is over an area where people may be standing, such as a sidewalk or patio
• the window frame is weak, loose, or old.
• you intend to leave it in place for an extended period of time
• you expect high wind or heavy snow
• you are required to use a bracket for your air conditioner
• you are on the 2nd floor or higher

This is not meant to be an exhaustive list. There may be other factors that necessitate screwing the mount securely in place.

What's your return policy?
We have a 1 month return policy. If you send the product back within a month of receiving it we will refund the cost. The product must not be missing any pieces or be damaged. The refund does not cover shipping. Please check that your window is the appropriate type and size for our mount before ordering to minimize the need for returns. Email yo@energytransitiondesign.com to request a return.

I have child-safety bars on my window. Can the mount still be installed?
Many child-safety bars use a similar installation method as our solar panel mount, so you probably wont be able to install our system if you have them in place. However, it depends on how your bars are installed.