While CityVille has already received a few Greenhouses, allowing you to grow specific sets of crops without taking up a lot of land space, apparently that's not enough for some veteran players, as Zynga is looking to help us out even more via the Super Solar Greenhouse. You'll only need to be at least Level 20 to receive this Greenhouse, which can be used to grow crops and save energy when you harvest them. Here's a complete look at the Super Solar Greenhouse, straight from Zynga.
Ask friends for 10 Solar Shears
Place and Complete the Super Solar Greenhouse
Harvest 25 Carrots
The Super Solar Greenhouse will only be available for a limited time, but it's definitely worth building in the long run, as it will allow you to save up to six energy when harvesting it, and can also grow any kind of crop. A base Super Solar Greenhouse requires building materials to complete and will save you two energy on each harvest. It will only hold a maximum of eight plots, but it can be upgraded in the long run. First things first, though, you'll need to finish the very first stage of the Greenhouse, which requires the following:
6 Orange Panels
6 Green Panels
6 Light Green Panels
6 Yellow Panels
6 Purple Panels
6 Blue Panels
These items are earned via a combination of individual requests sent to friends and general news posts placed on your wall. This goes for all colors except the Light Green Panel, which is earned as a bonus item that drops when tending either the Sunny Duplex or Green Gables buildings in your city. The Sunny Duplex costs coins, so at least everyone has access to them without City Cash.
After you've completed the first stage of the Super Solar Greenhouse, you'll be able to upgrade it to hold more plots by collecting more and more Panels in larger quantities.