As I wrote in my post about how to support clean energy if you can’t go solar, many of us do not have the luxury of a sunny roof — nor the money to spend on a full solar array. Heck, many of us rent and may not have a landlord who’s excited about sticking photovoltaic panels on the roof.

Nevertheless, we can all do our part to support a cleaner electric grid. One of the simplest ways is to put our savings and investments to work in support of renewables elsewhere.

Here are some innovative companies and investment platforms that can help you do just that.

Mosaic: Crowdfunded solar

California-based Mosaic has long been a pioneer in clean energy financing. As detailed in this interview with founder Billy Parish, the company is focused on lending to small- and medium-sized solar projects that banks are not set up to support. By connecting small investors with viable projects, Mosaic allows us ordinary folk to earn a return while financing others in their desire to go solar. Want to invest? Learn more here.

Wiser Capital: Empowering energy investors to go solar

Wiser Capital is working on a different piece of the puzzle, aiming to take the red tape and other administrative barriers out of the way for energy investors who may not be specializing in, or familiar with, solar power. (Interestingly, Wiser recently conducted research that suggests 83 percent of investors expect to make solar investing a priority in the next five years.)

Wiser Capital is aiming to facilitate this growth through a web-based platform that connects energy investors with small-to-medium sized facilities for hassle-free financing. The platform features independent and interactive solar analytics, investment grade financial modeling, and a risk rating tool called Wiser Solar Asset Rating (WSAR) Score, which automates the transaction process, calculating bankability and risk, while providing standardization, transparency and education too.

Abundance Generation: A virtual portfolio of projects

In the U.K., Abundance Generation has also been pursuing a crowdfunded approach to small-scale investing. Investors can upload money to their account using a credit or debit card, browse a selection of (often community-based) wind, solar and other renewable energy projects offering different risks/rates of return, read their “offer documents,” and then choose to fund any that strike their fancy. The terms of these “debentures” are often long-term investments, and there are risks of course — risks you wouldn’t face if simply depositing in a savings account, but annual returns can be as high as 9 percent on certain projects.

Wunder Capital: Detailed info for accredited investors

Much like Wiser, Wunder Capital is focused on accredited investors and uses a proprietary web platform to provide very specific information about a broad range of solar projects. Unlike conventional investment companies, which may not be set up to understand the details that impact success or failure of solar, Wunder looks at "underlying property fundamentals, such as vacancy rate, property value, and shade coverage instead of just credit scores." Selected projects are pooled into diversified online funds into which any accredited investor can commit as little as $1,000. Wunder says that it expects annual returns in the 6 percent range.

Re-Volv Solar Seed Fund: Donations as investment

For some people investing in solar, the specific rate of return is going to be important. For others, it's more about supporting a technology we desperately need to go mainstream. If you want to put your money to work for the long-term, but don't necessarily need to see any of it come back to you, then Re-Volv may be a good bet. As I mentioned in this article for TreeHugger, Re-Volv is a revolving solar seed fund. Donations, which are tax deductible, are used to finance solar installations on community groups and non-profits. Those community groups pay back the cost of the installation over time, from the savings on their energy bills. Re-Volv then uses the money that comes back to them to finance more installations elsewhere — eventually building a self-sustaining fund for community-based solar.

Disclaimer: I am not a financial journalist nor an investment adviser. Please consult a qualified financial adviser before making any significant financial decisions.