· Earth Day · Planning
Green City Builder: free city planning game with clean energy
Build a city that runs on clean energy and stays in budget.
What is Green City Builder?
Five town plans on small grids, from a riverside street to a net-zero town. Place homes, efficient homes, solar panels, wind turbines, gas plants and tram stops so there's enough housing and power, the cost stays within budget and emissions stay under the limit. The model and its numbers are made up and kept simple.
Green City Builder is a free Earth Day planning puzzle. Across five plans, from a riverside street to a net-zero town, you place homes, efficient homes, solar panels, wind turbines, gas plants and tram stops on a small map with hills, a river and protected forest.
Every plan has four goals: enough homes, enough power for everything you built, a budget in coins and an emissions limit. Live meters show each goal as you build. Wind is strong on hills but too noisy to sit next to homes, homes next to a tram stop leave the car at home, and gas is cheap but dirty. The model and its numbers are made up and simple, and every plan is proven solvable.
At a glance
- Category
- Seasonal
- Difficulty
- Hard
- Play time
- 5–7 min
- Price
- Free, in your browser, sign-up optional
How to play
- Read the goals
- Each plan sets the homes you need, a budget in coins and an emissions limit. Power must cover demand.
- Place tiles
- Pick a tile, then tap the map. Wind gives more on hills but can't touch homes; homes next to a tram stop are car-free.
- Balance it
- Gas is cheap but dirty, solar and wind are clean, efficient homes need less power. Live meters show every goal.
- Score
- 100 per town opened + 10 per coin left + 15 per emission under the limit, −25 per hint. Every plan is solvable.
Scoring
Each town you open scores 100, plus 10 per coin left in the budget and 15 per unit of emissions under the limit. Each hint costs 25.
Five plans; a skipped plan scores 0. Stars compare your score with the planner's best, which the game proves is reachable.
What it trains
- Sustainable planning
- Balancing housing, energy, budget and emissions at the same time.
- Trade-offs
- Cheap but dirty gas against clean solar and wind, and cutting demand with efficient homes and transit.
- Spatial reasoning
- Placing turbines away from homes and grouping homes around tram stops.
Strategy and tips
- Use the hills
- A turbine on a hill gives 5 power instead of 3, for the same cost.
- Keep turbines apart
- Wind can't share a side with a home, so plan a gap between them.
- One tram, four homes
- A tram stop makes every home that touches it car-free: put homes on all four sides.
- Cut demand first
- An efficient home needs 1 power instead of 2, often cheaper than building more power.
- Hints show a good plan
- Each hint places one tile of the planner's best plan, for 25 points.
Why play Green City Builder?
Real planning is about trade-offs: money, energy, transport and emissions all pull in different directions. Green City Builder turns that into a small puzzle you can hold in your head, so you practise weighing several goals at once and see why clean power, efficient buildings and transit work best together.
Frequently asked questions
Is Green City Builder free?
Yes. It is free and runs in your browser, with no download. Signing up is optional.
Are the numbers realistic?
No: the model and its numbers are made up and kept simple. The trade-offs it shows, like cheap but dirty gas or transit cutting car trips, are the real lessons.
What if I get stuck?
Use a hint (−25 points), which places one tile of a best plan, or skip the plan. After each plan, the planner's best layout is shown.
Can I play with a keyboard or a screen reader?
Yes. Keys 1 to 7 pick a tile, every map cell is a button that says its terrain and tile, and the goals are announced after each change.